# AquaCalc
> A free, privacy-first water chemistry toolkit for planted aquarium enthusiasts.
> Twelve free calculators — tank volume, substrate, filter capacity, CO₂ cylinder runtime, drop checker, fertiliser comparison, fish and plant lookup, heat forecast, parameter log and maintenance schedule — plus a My Tank dashboard (pH/CO₂ monitoring, RO water mixing, fertiliser dosing, water changes). Sixteen tools in all.
> No account required. All data saved locally per tank profile. Based in the UK.
> Full article text in Markdown: [llms-full.txt](https://www.aquacalc.uk/llms-full.txt) — individual articles are also available as Markdown at <article-url>.md

## Tools
- [My Tank dashboard](https://www.aquacalc.uk/dashboard/): pH/CO₂ monitoring, RO water mixing, fertiliser dosing and water changes, saved per tank profile
- [All calculators hub](https://www.aquacalc.uk/tools.php)
- [UK aquarium shops & suppliers map](https://www.aquacalc.uk/shops.php): a community-maintained map of recommended aquarium shops, plant and hardscape stockists, CO₂ refills and breeders across the UK — searchable and filterable by type, with community suggestions and "report closed" moderation; seeded from the UKAPS recommended-shops map by Meg / the UK Aquatic Plant Society
- [UK aquarium plant price comparison](https://www.aquacalc.uk/plant-price-compare.php): prices and stock for the same plant across seven UK plant shops - Aqua Essentials, Aquarium Gardens, Cloud Aqua, Horizon Aquatics, Pro Shrimp, Dennerle Plants and Aquascaping Express - matched on species AND form so a tissue-culture cup is never priced against a potted plant; includes an order planner that works out the cheapest combination of shops with postage and free-delivery thresholds included; refreshed several times a day; no affiliate links or commission
- [Tank Kit Builder](https://www.aquacalc.uk/tank-kit.php): guided wizard that recommends an aquarium equipment checklist — filter, heater, substrate, CO₂, lighting, testing and treatments — sized to the tank; rules-based, no personal data
- [pH Method Finder](https://www.aquacalc.uk/ph-method-finder.php): pick your water type and goal, and it names the pH-measurement method the science supports — cheap glass pen, CO₂ drop checker, inference from KH + conductivity, or spectrophotometric — with honest caveats; companion to the "Measuring pH" article
- [Tank volume calculator](https://www.aquacalc.uk/tank-volume-calculator.php): rectangle, bowfront, hex, corner, cylinder, sphere — adjusts for substrate, hardscape and filter volume
- [Substrate calculator](https://www.aquacalc.uk/substrate-calculator.php): volume, weight, bag count for ADA, Tropica, Fluval Stratum, UNS Controsoil and more; flat and sloped layouts
- [CO₂ cylinder runtime estimator](https://www.aquacalc.uk/co2-cylinder-calculator.php): days remaining, run-out date, reorder reminder from weight, bubble rate and diffuser type
- [Fertiliser comparison calculator](https://www.aquacalc.uk/fertiliser-comparison.php): compare branded aquarium plant fertilisers — NPK and micronutrients each delivers in ppm at the manufacturer's recommended dose or a custom dose, for any tank size; data from manufacturer guaranteed analyses
- [Filter capacity calculator](https://www.aquacalc.uk/filter-capacity-calculator.php): biological surface area and fish load by media type — based on aquariumscience.org data
- [Aquarium teardown planner](https://www.aquacalc.uk/aquarium-teardown-planner.php): plan a safe teardown for rotating, replacing or rescaping a tank — sizes holding tubs from your own livestock, gives real weights and a time estimate, and runs an adaptive checklist with a livestock welfare timer that saves progress as you go
- [Drop checker colour guide](https://www.aquacalc.uk/drop-checker-guide.php): personalised colour reference by KH; flags visually indistinguishable CO₂ ranges
- [Fish species lookup](https://www.aquacalc.uk/fish-lookup.php): temperature, pH, hardness, tank size — data from FishBase
- [Plant species lookup](https://www.aquacalc.uk/plant-lookup.php): light level, CO₂ requirement, water parameters, growth rate and placement for 140+ aquarium plants
- [Aquarium heat forecast](https://www.aquacalc.uk/aquarium-heat-forecast.php): 14-day temperature outlook with Good / Warming / Extreme risk indicators for any location worldwide
- [Parameter log](https://www.aquacalc.uk/parameter-log.php): record water test results for any parameter — nitrate, pH, ammonia and more — and view them as graphs over time
- [Maintenance schedule](https://www.aquacalc.uk/maintenance-schedule.php): plan a full recurring maintenance routine per tank — water changes, dosing, filter cleaning, testing and more — on a visual calendar; saves to your account with reminders

## Science articles
In-depth guides on aquarium chemistry, biology, and planted tank practice.

- [CO₂ at the leaf: the physics of carbon starvation in planted aquariums](https://www.aquacalc.uk/blog/co2-leaf-boundary-layer): CO₂ boundary layer physics — why 30 ppm CO₂ in bulk water is not 30 ppm at the leaf surface, diffusion rates in water vs air, boundary layer thickness, circulation and flow implications for planted tanks
- [Active substrates and CEC: the science of how aquarium soils work, how hard water degrades them, and what happens when they age](https://www.aquacalc.uk/blog/aquarium-substrate-cec): Active substrates and CEC — cation exchange capacity, how volcanic soils buffer pH and release nutrients, why hard water degrades CEC faster, what happens as aquasoil ages
- [Aquarium surface agitation: the physics of how oxygen enters water](https://www.aquacalc.uk/blog/aquarium-surface-agitation): Aquarium surface agitation — gas transfer physics (surface renewal theory), when flat surfaces are safe in planted tanks vs. when they risk overnight hypoxia, the CO₂ timer trap
- [Dissolved oxygen in aquariums: what the thresholds mean and what low levels do to fish](https://www.aquacalc.uk/blog/dissolved-oxygen): Dissolved oxygen in aquariums — saturation thresholds, diurnal DO cycle in planted tanks, what chronic hypoxia does to fish immunity and growth
- [KH, GH and the CO₂–pH triangle: the carbonate chemistry your aquarium relies on](https://www.aquacalc.uk/blog/kh-co2-ph): KH, GH and the CO₂–pH triangle — carbonate buffering chemistry, why KH (not GH) controls pH stability, where the CO₂ triangle breaks down, pH crashes in soft water
- [Heat stress in aquariums: the science of what extreme temperatures do to your fish and water](https://www.aquacalc.uk/blog/heatwave): Heatwave and heat stress — the physics of how outdoor temperatures heat tank water, the oxygen squeeze (Henry's Law + Q10 metabolic rate), ammonia toxicity at high temperature, and evidence-graded coping strategies
- [Plant melt: why your new aquarium plants are dissolving — and why that is normal](https://www.aquacalc.uk/blog/plant-melt): Plant melt — why emersed-grown and tissue culture plants dissolve after planting, what heterophylly is, and when to worry vs. wait
- [Water changes: what the science actually says about frequency, volume, and the fear of killing fish](https://www.aquacalc.uk/blog/water-changes): Water changes — frequency, volume, nitrate science, and the "large water change kills fish" myth
- [Lily pipe placement: the geometry of whole-tank CO₂ distribution](https://www.aquacalc.uk/blog/lily-pipe-placement): Lily pipe placement — gyre geometry, Coanda effect, inlet/outlet positioning for whole-tank CO₂ distribution
- [Black beard algae: what the science says, what is debated, and what actually works](https://www.aquacalc.uk/blog/black-beard-algae): Black beard algae — CO₂ instability as cause, H₂O₂ and glutaraldehyde treatments, what is evidence vs. hypothesis
- [Flow in a planted tank: why the 10× rule was never about your plants](https://www.aquacalc.uk/blog/aquarium-flow): Aquarium flow — why the 10× turnover rule was never about plants, what flow actually does for CO₂
- [What "stable CO₂" actually means — busting the 30ppm myth](https://www.aquacalc.uk/blog/co2-stability): CO₂ stability — what "stable CO₂" really means and why a fixed 30ppm target is a myth
- [Comammox: the bacteria rewriting the nitrogen cycle](https://www.aquacalc.uk/blog/comammox): Comammox bacteria — the organism that completes the nitrogen cycle in one step, and what it means for cycling
- [Chlorine & chloramines: the danger hiding in your tap](https://www.aquacalc.uk/blog/chlorine): Chlorine and chloramines — why tap water is more acutely dangerous than ammonia, and how to make it safe
- [UV sterilisers: what they actually kill — and what they don't](https://www.aquacalc.uk/blog/uv-steriliser-science): UV sterilisers and inactivation — what UV actually kills (Cryptosporidium, algae, bacteria) and what it doesn't (Adenovirus, encysted stages, dissolved chemistry), based on Hijnen et al. (2006)
- [UV dose: why flow rate matters more than watt rating](https://www.aquacalc.uk/blog/uv-steriliser-sizing): UV steriliser sizing and dose — flow rate as the key variable (not wattage), dose requirements per organism, lamp aging, turbidity effects
- [Where fish waste actually goes: the nitrogen cycle in a closed aquarium](https://www.aquacalc.uk/blog/nitrogen-waste-aquarium): Nitrogen waste in closed aquariums — 60–90% dissolved as ammonia, nitrification chain, why nitrate accumulates, what plants and water changes actually do, based on van Rijn (2013)
- [Chelated iron in planted aquariums: why Fe-EDTA fails at neutral pH](https://www.aquacalc.uk/blog/chelated-iron-aquarium): Science-backed guide to iron chelation in planted aquariums: why Fe-EDTA fails above pH 7.0, how Fe-DTPA and Fe-EDDHA differ, and how to choose the right chelate for your tank's pH range.
- [Hornwort (Ceratophyllum demersum): the fast-growing water purifier](https://www.aquacalc.uk/plants/hornwort): Hornwort (Ceratophyllum demersum) plant profile covering its exceptional growth rate, water-purifying properties, floating vs anchored placement, allelopathic effects, and why it sheds needles.
- [Pogostemon helferi (Downoi): the star-shaped foreground plant](https://www.aquacalc.uk/plants/pogostemon-helferi): Pogostemon helferi (Downoi) care guide covering star-shaped rosette growth, Thai river origins, flow requirements, CO2 recommendations, and foreground placement
- [Bacopa caroliniana: the classic lemon-scented stem plant](https://www.aquacalc.uk/plants/bacopa-caroliniana): Bacopa caroliniana care guide covering slow steady growth, lemon monoterpene scent, low light tolerance, stem trimming and replanting, and comparison with faster stem plants
- [Hygrophila polysperma: the ultimate beginner stem plant](https://www.aquacalc.uk/plants/hygrophila-polysperma): Hygrophila polysperma care guide covering extreme adaptability, fast growth rate, pink variegated form, invasive status in some regions, and maintenance
- [Water Wisteria (Hygrophila difformis): the shape-shifting stem plant](https://www.aquacalc.uk/plants/water-wisteria): Water wisteria (Hygrophila difformis) care guide covering leaf heterophylly, fast growth, low light tolerance, and nutrient stripping
- [Tiger Lotus (Nymphaea zenkeri): the statement bulb plant](https://www.aquacalc.uk/plants/tiger-lotus): Tiger lotus (Nymphaea zenkeri) care guide covering bulb planting, surface pad management, red vs green forms, and why trimming keeps it compact
- [Bucephalandra: the jewel plant from Borneo](https://www.aquacalc.uk/plants/bucephalandra): Bucephalandra care guide covering rheophyte origins, iridescent leaf coloration, hardscape attachment, slow growth rate, and variety overview
- [Alternanthera reineckii: bringing red into the planted tank](https://www.aquacalc.uk/plants/alternanthera-reineckii): Alternanthera reineckii care guide covering red coloration, light and phosphate requirements, stem trimming, and variety differences (Mini vs standard)
- [Staurogyne repens: the forgiving foreground plant](https://www.aquacalc.uk/plants/staurogyne-repens): Staurogyne repens care guide covering foreground placement, trimming technique, moderate light needs, and comparison with carpeting alternatives
- [HC Cuba (Hemianthus callitrichoides): the ultimate carpet plant](https://www.aquacalc.uk/plants/hc-cuba): HC Cuba (Hemianthus callitrichoides) care guide covering carpet growth, high-light CO2 requirements, substrate selection, and melting after purchase
- [Dwarf sagittaria (Sagittaria subulata): the low-tech carpet](https://www.aquacalc.uk/plants/dwarf-sagittaria): Dwarf sagittaria (Sagittaria subulata) care guide covering its grassy runner-spreading carpet habit, low-tech carpeting without CO2, how light controls its height, root feeding, brackish tolerance, and propagation by stolons
- [Anacharis (Egeria densa): the classic beginner oxygenator](https://www.aquacalc.uk/plants/anacharis): Anacharis (Egeria densa) care guide covering whorled leaves, very fast growth, cold tolerance, nutrient stripping, biogenic decalcification and its invasive-species status
- [Water sprite (Ceratopteris thalictroides): float it or plant it](https://www.aquacalc.uk/plants/water-sprite): Water sprite (Ceratopteris thalictroides) care guide covering its lacy fern fronds, dual planted-or-floating habit, fast nutrient-stripping growth, fry cover, and self-propagation via plantlets on the leaf margins
- [Amazon frogbit (Limnobium laevigatum): the easy floating plant](https://www.aquacalc.uk/plants/amazon-frogbit): Amazon frogbit (Limnobium laevigatum) care guide covering floating rosettes, trailing roots as fry and shrimp cover, fast growth, heavy nitrate and iron uptake, surface shading trade-offs, and how to stop leaves rotting
- [Marimo moss ball (Aegagropila linnaei): care, cleaning and myths](https://www.aquacalc.uk/plants/marimo-moss-ball): Marimo moss ball (Aegagropila linnaei) care guide explaining that it is a rare ball-forming green alga (not moss or a plant), how to roll and clean it, its very slow growth and cold tolerance, and how to diagnose browning or bleaching
- [Water lettuce (Pistia stratiotes): the big-rooted floater](https://www.aquacalc.uk/plants/water-lettuce): Water lettuce (Pistia stratiotes) — the velvety floating rosette with long fry-sheltering roots.
- [Red root floaters (Phyllanthus fluitans): the red surface jewel](https://www.aquacalc.uk/plants/red-root-floaters): Red root floaters (Phyllanthus fluitans) — the red-blushing nano floating plant and how to colour it up.
- [Madagascar lace plant (Aponogeton madagascariensis): living lattice](https://www.aquacalc.uk/plants/madagascar-lace): Madagascar lace plant (Aponogeton madagascariensis) — the skeletal-leaved specimen bulb and how to keep it.
- [Guppy grass (Najas guadalupensis): the breeder's best friend](https://www.aquacalc.uk/plants/guppy-grass): Guppy grass (Najas guadalupensis) — the fast, floating-or-planted fry-cover and nutrient sponge.
- [Duckweed (Lemna minor): friend, foe and nutrient sponge](https://www.aquacalc.uk/plants/duckweed): Duckweed (Lemna minor) — the tiny floating nutrient sponge, its uses and how to control it.
- [Floating fern (Salvinia natans): the water spangle floater](https://www.aquacalc.uk/plants/salvinia-natans): Salvinia natans (floating fern / water spangles) — the fast floating fern for shade and nutrient export.
- [Rotala wallichii: the pink needle stem](https://www.aquacalc.uk/plants/rotala-wallichii): Rotala wallichii — the delicate high-tech stem with pink-to-red needle whorls.
- [Crystalwort (Riccia fluitans): the pearling carpet moss](https://www.aquacalc.uk/plants/riccia-fluitans): Riccia fluitans (crystalwort) — the bright liverwort tied down as a pearling aquascaping carpet.
- [Micro sword (Lilaeopsis brasiliensis): the grassy carpet](https://www.aquacalc.uk/plants/micro-sword): Micro sword (Lilaeopsis brasiliensis) — the short, runner-spreading grassy carpet plant.
- [Rotala macrandra: the giant red rotala that tests every scaper](https://www.aquacalc.uk/plants/rotala-macrandra): Rotala macrandra (giant red rotala): a demanding red stem plant needing high light, CO2, lean nitrate and stable soft water for deep pink-red colour.
- [Pogostemon stellatus (Octopus plant): the big-whorled background stem](https://www.aquacalc.uk/plants/pogostemon-stellatus): Pogostemon stellatus (octopus plant): a fast whorled background stem needing high light, CO2, steady macros and some GH; prone to stunting when nutrients dip.
- [Myriophyllum mattogrossense: the feathery green foxtail for fast growth](https://www.aquacalc.uk/plants/myriophyllum-mattogrossense): Myriophyllum mattogrossense (green foxtail): a fast feathery column feeder useful for outcompeting algae in new tanks; needs good light and iron to stay green.
- [Hygrophila corymbosa (Temple plant): the easy big-leaved background stem](https://www.aquacalc.uk/plants/hygrophila-corymbosa): Hygrophila corymbosa (temple plant): a fast, hardy big-leaved background stem for beginners; tolerates low light and hard water; watch for potassium pinholes.
- [Ludwigia arcuata: the fine needle-leaf ludwigia that burns orange-red](https://www.aquacalc.uk/plants/ludwigia-arcuata): Ludwigia arcuata (needle-leaf ludwigia): a hardy fine-leaved colour stem that flushes orange-red under high light and lean nitrogen; green in low light.
- [Limnophila aromatica: the purple-backed stem that started as a kitchen herb](https://www.aquacalc.uk/plants/limnophila-aromatica): Limnophila aromatica (purple ambulia / rice paddy herb): a forgiving colour stem with green tops and purple undersides under strong light and lean nitrogen.
- [Dwarf four-leaf clover (Marsilea hirsuta): the low-tech carpet](https://www.aquacalc.uk/plants/marsilea-hirsuta): Marsilea hirsuta — the hardy four-leaf-clover carpet that grows without CO2.
- [Ludwigia super red (Ludwigia palustris): the easy red stem](https://www.aquacalc.uk/plants/ludwigia-super-red): Ludwigia super red (Ludwigia palustris) — the beginner-friendly deep-red stem plant.
- [Asian ambulia (Limnophila sessiliflora): the feathery fast stem](https://www.aquacalc.uk/plants/limnophila-sessiliflora): Asian ambulia (Limnophila sessiliflora) — the fast, feathery background stem that grows without CO2.
- [Micranthemum umbrosum (Shade mudflower): the bright round-leaved carpet stem](https://www.aquacalc.uk/plants/micranthemum-umbrosum): Micranthemum umbrosum (shade mudflower): a bright round-leaved stem for midground or a loose carpet; despite the name it needs good light and benefits from CO2 to stay dense rather than leggy.
- [Lobelia cardinalis (Cardinal flower): the round-leaved midground with coloured undersides](https://www.aquacalc.uk/plants/lobelia-cardinalis): Lobelia cardinalis (cardinal flower): the aquarium small form is an easy round-leaved midground with green tops and reddish-purple undersides; often sold emersed and may melt before adapting to submersed growth.
- [Water violet (Hottonia palustris): the feathery temperate stem](https://www.aquacalc.uk/plants/hottonia-palustris): Hottonia palustris (water violet): a feathery temperate stem for cool water and unheated tanks; prefers below ~25C and struggles in warm tropical tanks; European native, forms winter turions.
- [Cryptocoryne undulata (Undulate crypt): the wavy-leaved easy crypt](https://www.aquacalc.uk/plants/cryptocoryne-undulata): Cryptocoryne undulata (undulate crypt): an easy, faster-than-average rosette crypt with wavy strap leaves for the midground; a root feeder tolerant of a wide pH range and prone to crypt melt when moved.
- [Hygrophila pinnatifida: the fern-leaved epiphyte stem](https://www.aquacalc.uk/plants/hygrophila-pinnatifida): Hygrophila pinnatifida — the serrated fern-leaved plant that plants or attaches to wood, with bronze-red tones.
- [Brazilian pennywort (Hydrocotyle leucocephala): the round-leaved climber](https://www.aquacalc.uk/plants/hydrocotyle-leucocephala): Brazilian pennywort (Hydrocotyle leucocephala) — the fast, round-leaved stem that grows planted, climbing or floating.
- [Glossostigma elatinoides: the demanding show carpet](https://www.aquacalc.uk/plants/glossostigma-elatinoides): Glossostigma elatinoides (glosso) — the high-light, CO2-demanding bright-green aquascaping carpet.
- [Cryptocoryne parva: the smallest crypt](https://www.aquacalc.uk/plants/cryptocoryne-parva): Cryptocoryne parva — the smallest Cryptocoryne, a slow low-light foreground rosette.
- [Cryptocoryne balansae: the corrugated background crypt](https://www.aquacalc.uk/plants/cryptocoryne-balansae): Cryptocoryne balansae — the tall, corrugated-leaf crypt for the background, tolerant of hard water.
- [African water fern (Bolbitis heudelotii): the dark lace epiphyte](https://www.aquacalc.uk/plants/bolbitis-heudelotii): African water fern (Bolbitis heudelotii) — the slow, dark lacy-fronded epiphyte fern for wood.
- [Banana plant (Nymphoides aquatica): the curious tuber plant](https://www.aquacalc.uk/plants/banana-plant): Banana plant (Nymphoides aquatica) — the easy novelty plant with banana-like tubers and heart-shaped leaves.
- [Aponogeton crispus: the easy crinkled bulb plant](https://www.aquacalc.uk/plants/aponogeton-crispus): Aponogeton crispus — the easy crinkled-leaf bulb plant for the background, no CO2 needed.
- [Christmas moss (Vesicularia montagnei): the drooping fir-tree moss](https://www.aquacalc.uk/plants/christmas-moss): Christmas moss (Vesicularia montagnei) — the dense fir-tree-shaped moss for wood, rock and moss walls.
- [Cabomba (Cabomba caroliniana): the classic feathery bunch plant](https://www.aquacalc.uk/plants/cabomba-caroliniana): Cabomba caroliniana (green cabomba) — the classic feathery fan-leaved bunch plant and how to keep it lush.
- [Blyxa japonica: the grassy bush that blushes bronze](https://www.aquacalc.uk/plants/blyxa-japonica): Blyxa japonica — the grassy rosette bush that turns bronze-red under high light and lean nutrients.
- [Anubias barteri: the bigger, bulletproof epiphyte](https://www.aquacalc.uk/plants/anubias-barteri): Anubias barteri — the larger, near-indestructible epiphyte with broad leaves on a rhizome.
- [Moneywort (Bacopa monnieri): the tough round-leaved stem](https://www.aquacalc.uk/plants/bacopa-monnieri): Bacopa monnieri (moneywort) — the near-indestructible round-leaved beginner stem plant.
- [Java fern 'Windelov': the lace-tipped epiphyte fern](https://www.aquacalc.uk/plants/java-fern-windelov): Java fern 'Windelov' (Leptochilus pteropus 'Windelov'): an easy, low-light epiphyte fern with finely forked, lacy leaf tips; attach it to wood or rock and never bury the rhizome. Propagates from plantlets on mature leaves.
- [Cryptocoryne 'Flamingo': the pink crypt for the patient](https://www.aquacalc.uk/plants/cryptocoryne-flamingo): Cryptocoryne 'Flamingo': a striking pink-to-magenta Cryptocoryne wendtii cultivar; slow-growing and unusually demanding for a crypt, needing strong light, a nutrient-rich root zone and very stable conditions to hold its colour.
- [Star grass (Heteranthera zosterifolia): the bushy, fast-growing green filler](https://www.aquacalc.uk/plants/star-grass): Star grass (Heteranthera zosterifolia): a fast, bushy, light-green stem plant for the midground and background; easy and CO2-optional, but needs decent light to stay dense rather than stretched and leggy.
- [Rotala 'H'ra': the fiery orange-red aquascaping stem](https://www.aquacalc.uk/plants/rotala-hra): Rotala 'H'ra': a fine-leaved Rotala rotundifolia form that turns orange to fiery red under strong light and CO2; a fast, popular aquascaping background red that stays green in low light and lean tanks.
- [Pogostemon erectus: the bright-green bottlebrush stem](https://www.aquacalc.uk/plants/pogostemon-erectus): Pogostemon erectus: a stiff, bright-green bottlebrush stem plant for the midground; grows compact and upright and shows its best form with strong light and CO2. Medium difficulty rather than a beginner plant.
- [Hydrocotyle tripartita 'Japan': the versatile trilobed creeper](https://www.aquacalc.uk/plants/hydrocotyle-tripartita): Hydrocotyle tripartita 'Japan': a fast, easy creeping plant with tiny trilobed leaves that can be grown as a bright foreground carpet, a climber over hardscape, or a midground filler; light and trimming decide whether it stays low.
- [Pearlweed (Micranthemum micranthemoides): the fast, versatile bright-green filler](https://www.aquacalc.uk/plants/pearlweed): Pearlweed (Micranthemum micranthemoides): a fast, easy, bright-green stem plant that grows as a background bush, midground accent or trimmed foreground carpet across low to high light; note the long-standing taxonomic confusion with the possibly-extinct Hemianthus micranthemoides.
- [Dwarf chain sword (Helanthium tenellum): the grassy runner carpet](https://www.aquacalc.uk/plants/dwarf-chain-sword): Dwarf chain sword (Helanthium tenellum, formerly Echinodorus tenellus): an easy grass-like carpet plant that spreads by runners; height is light-driven, staying short and lawn-like under strong light and growing taller in shade.
- [Creeping Jenny (Lysimachia nummularia): the golden-green low stem](https://www.aquacalc.uk/plants/creeping-jenny): Creeping Jenny (Lysimachia nummularia 'Aurea'): an easy golden-green stem plant for the foreground and midground; the gold colour is driven by strong light. It is a bog/marginal plant grown submersed, and is invasive on land in parts of North America — never release it.
- [Java fern 'Trident': the forked, antler-leaved fern](https://www.aquacalc.uk/plants/java-fern-trident): Java fern 'Trident' (Leptochilus pteropus 'Trident'): an easy, low-light epiphyte fern whose leaves split into slender forked lobes; attach it to wood or rock and never bury the rhizome. Propagates from plantlets on mature leaves.
- [Ammannia gracilis: the graceful red-orange background stem](https://www.aquacalc.uk/plants/ammannia-gracilis): Ammannia gracilis: a tall, graceful background stem plant that shades from olive green to orange-red; the warm colour depends on strong light and CO2, so it is a medium-difficulty plant for high-tech tanks.
- [Java fern 'Narrow': the slender strap-leaved fern](https://www.aquacalc.uk/plants/java-fern-narrow): Java fern 'Narrow' (Leptochilus pteropus 'Narrow Leaf'): an easy, low-light epiphyte fern with long, slim strap leaves; attach it to wood or rock and never bury the rhizome. Propagates from plantlets on mature leaves.
- [Anubias 'Petite': the miniature nano epiphyte](https://www.aquacalc.uk/plants/anubias-nana-petite): Anubias 'Petite' (Anubias barteri var. nana 'Petite'): the smallest anubias — a tiny, bulletproof low-light epiphyte for nano tanks and foregrounds; attach it to wood or rock and never bury the rhizome. No CO2 needed; propagates by rhizome division.
- [Anubias 'Mini Coin': the round-leaved nano epiphyte](https://www.aquacalc.uk/plants/anubias-mini-coin): Anubias 'Mini Coin' (Anubias barteri var. nana 'Mini Coin'): a small, tough low-light epiphyte with distinctive round, coin-shaped leaves; attach it to wood or rock and never bury the rhizome. No CO2 needed; propagates by rhizome division.
- [Weeping moss (Vesicularia ferriei): the drooping hardscape moss](https://www.aquacalc.uk/plants/weeping-moss): Weeping moss (Vesicularia ferriei): an easy, low-light aquarium moss whose mature fronds droop in a weeping cascade; attach it to wood or rock (no substrate), no CO2 needed. Used for moss 'trees' and draped driftwood. Propagates by division.
- [Bucephalandra 'Kedagang': the dark, narrow-leaved jewel](https://www.aquacalc.uk/plants/bucephalandra-kedagang): Bucephalandra 'Kedagang' (Family Araceae, Borneo): a slow, tough epiphyte with narrow, wavy, dark-green iridescent-flecked leaves; attach it to wood or rock and never bury the rhizome. No CO2 required (beneficial); propagates by rhizome division.

## Plant Insights
Science-grounded species profiles covering care requirements, light, CO2, substrate, and what makes each plant thrive or struggle.
- [Plants hub](https://www.aquacalc.uk/plants/)

- [Amazon Sword (Echinodorus grisebachii): the plant that started planted tanks](https://www.aquacalc.uk/plants/amazon-sword): Amazon Sword (Echinodorus grisebachii 'Bleherae') care guide — large rosette from South America, heavy root feeder (root tabs needed in inert substrates), low to medium light, no CO2 required, moderate growth, emersed leaves die off after purchase which is normal, iron deficiency causes yellow leaves with green veins
- [Anubias barteri var. nana: the indestructible epiphyte](https://www.aquacalc.uk/plants/anubias-nana): Anubias barteri var. nana care guide — rheophyte epiphyte from West Africa, very low light, no CO2 needed, attaches to hardscape, never bury rhizome
- [Cryptocoryne wendtii: rosette, runner, survivor](https://www.aquacalc.uk/plants/cryptocoryne-wendtii): Cryptocoryne wendtii care guide — Sri Lanka endemic, low-medium light, no CO2 required, root feeder, crypt melt is leaf response not death
- [Eleocharis parvula (Dwarf Hairgrass): the carpet that tests patience](https://www.aquacalc.uk/plants/eleocharis-parvula): Eleocharis parvula (Dwarf Hairgrass) care guide — foreground carpet plant, needs high light at substrate level and CO2 injection to spread; etiolates without sufficient light
- [Java Fern (Leptochilus pteropus): the fern fish won't eat](https://www.aquacalc.uk/plants/java-fern): Java Fern (Microsorum pteropus) care guide — attach to hardscape not substrate, very low light, no CO2 needed, slow grower, propagates from rhizome division
- [Java Moss (Taxiphyllum barbieri): the moss that goes anywhere](https://www.aquacalc.uk/plants/java-moss): Java Moss (Taxiphyllum barbieri) care guide — attaches to any surface, extremely low light, no CO2 needed, fast grower, useful for fry refuges and moss walls
- [Ludwigia repens: the red stem plant that does not need CO2](https://www.aquacalc.uk/plants/ludwigia-repens): Ludwigia repens care guide — fast-growing red stem plant from North America, no CO2 required, red colour driven by light intensity and iron availability (not CO2), leaf undersides always red, moderate to high light needed, fast grower requiring regular trimming, propagate by stem cuttings
- [Monte Carlo (Micranthemum tweediei): the honest carpet plant guide](https://www.aquacalc.uk/plants/monte-carlo): Monte Carlo (Micranthemum tweediei) care guide — fine-leafed carpet plant from Argentina, moderate to high light needed at substrate level, CO2 strongly recommended for lateral spreading (grows upward without it), fine aquasoil substrate required, plant deeply to prevent floating, trim regularly
- [Rotala rotundifolia: the colour-shifting stem plant](https://www.aquacalc.uk/plants/rotala-rotundifolia): Rotala rotundifolia care guide — colour shifts green to red with light/CO2/phosphate; CO2 injection needed for red colour; stem cuttings for propagation
- [Vallisneria spiralis: the original background plant](https://www.aquacalc.uk/plants/vallisneria-spiralis): Vallisneria spiralis care guide — fast-growing background plant, tolerates hard water, killed by glutaraldehyde liquid carbon products (Easycarbo/Excel)
- [Feeding Aquarium Fish: Food Types, Quantities and the Planted Tank Nitrogen Budget](https://www.aquacalc.uk/blog/fish-feeding): Science-backed guide to feeding aquarium fish: food types (dry, frozen, live, vegetable), calculating daily rations by body weight, Q10 temperature effects, ammonia production formula (TAN = food x protein% x 0.136), nitrogen budget in planted tanks, and how overfeeding drives algae in CO2-injected setups.
- [Aquarium Filter Media: What the Science Actually Says About Effectiveness](https://www.aquacalc.uk/blog/filter-media): Aquarium filter media compared by science — why manufacturer BET surface-area figures overstate usable bacterial area; the engineering metrics that matter (effective specific surface area from MBBR research, Ødegaard/NTNU; areal nitrification rate ~0.2-1.0 g TAN/m2/day from RAS studies); the honest evidence gap (no peer-reviewed head-to-head of hobby media brands; Scagnelli et al tested bottled bacteria; comammox described 2015); per-litre comparison of sponge, ceramic, sintered glass, bio-balls, moving-bed K1/K3 and porous rock
- [Dissolved Organics in the Aquarium: What DOC Really Is and Whether It Deserves Its Bad Reputation](https://www.aquacalc.uk/blog/dissolved-organics-aquarium): Dissolved Organics in the Aquarium: what dissolved organic carbon (DOC) is, the difference between labile and refractory fractions, what it can and cannot cause (oxygen demand, bacterial blooms, colour — not algae directly), the benefits of humic substances, and evidence-ranked control methods.
- [The Duckweed Index: Reading Your Water Through a Floating Plant](https://www.aquacalc.uk/blog/duckweed-index): The Duckweed Index: an admiring explainer of Darrel (dw1305)'s UKAPS technique for reading aquarium nutrient status from a floating plant's leaf colour and growth rate. Covers the 'aerial advantage' (floating leaves access atmospheric CO2), the rice Leaf Colour Chart origins, how to use it, why Amazon frogbit is preferred, mobile vs immobile nutrients, and the iron exception / Hybrid Duckweed Index.
- [CO2 Reactors: Bubble-Free CO2 for the Planted Tank](https://www.aquacalc.uk/blog/co2-reactor): CO2 Reactors: what an inline CO2 reactor is and how it dissolves CO2 completely for a bubble-free planted tank. Covers the gas-transfer physics (Henry's law, interfacial area vs contact time, boundary layer), reactor types (media/Cerges/internal), pros (no mist, high efficiency, even distribution) and cons (flow restriction, the gas-pocket 'burp', filter-off risk), and reactor vs diffuser.
- [Does it matter when you dose? Nutrient uptake in planted aquariums](https://www.aquacalc.uk/blog/nutrient-uptake-dosing-timing): Does dosing timing matter, and does early dosing feed algae? How aquarium plants take up nutrients via roots and leaves, why the water column is a reservoir, why time-of-day dosing barely matters (bar a minor iron caveat), and why a pre-dawn dose does not feed algae — algae need light too.
- [How to prepare and plant new aquarium plants](https://www.aquacalc.uk/blog/preparing-and-planting-new-aquarium-plants): Preparing and planting new aquarium plants: how to handle potted (rockwool), tissue-culture and bunched or clip-on epiphyte plants, correct planting depth, and why new plants melt before regrowing a submerged form.
- [How much light do my aquarium plants actually need?](https://www.aquacalc.uk/blog/how-much-light-do-aquarium-plants-need): a practical guide to PAR, PPFD and DLI, judging low/medium/high light without a meter, tank-depth effects, photoperiod, and a beginner starter protocol.
- [Do you really need to acclimatise new fish? What the science says](https://www.aquacalc.uk/blog/acclimatising-new-fish): Do you need to acclimatise new fish? The science of the three changes a fish faces moving from bag to tank — temperature, dissolved-ion/osmotic shock, and the bag-ammonia trap where a slow drip raising pH converts safe ammonium into toxic ammonia — and why both plop-and-drop and drip acclimation can be correct.
- [Paludariums for beginners: building your first hybrid aquatic-terrestrial tank](https://www.aquacalc.uk/blog/paludarium-beginners-guide): A beginner's guide to building a paludarium (hybrid aquatic-terrestrial tank): the false-bottom drainage layer, humidity and ventilation, filtration, and the amphibious plants that grow both submersed and emersed.
- [Fish quarantine: the science, and when it can be skipped](https://www.aquacalc.uk/blog/fish-quarantine-science): A balanced, science-backed examination of aquarium fish quarantine: what it biologically prevents, why many fishkeepers skip it and stay healthy (endemic stability, opportunistic pathogens, stress and immunity), why even a three-week quarantine can still fail, and how to weigh the risk for your own tank.
- [Cloudy aquarium water: what a bacterial bloom really means](https://www.aquacalc.uk/blog/cloudy-aquarium-water): Cloudy aquarium water explained: milky water is a heterotrophic bacterial bloom caused by more labile organic food in the water column than the filter biofilm can consume. Covers the triggers (new tank, overfeeding, over-cleaning the filter, medication, decay), the three ways it can affect fish (oxygen draw-down is the acute risk; ammonia/nitrite is the common co-symptom; raised pathogen exposure via r-selection for opportunists is the slow risk), why sterilising and scrubbing the filter backfires, and the practical fix — test, aerate, feed less, leave the filter alone, wait.
- [Chemical filter media: what is worth using, and what is a waste](https://www.aquacalc.uk/blog/chemical-filter-media): Chemical filter media guide: what activated carbon, Purigen, phosphate removers (GFO) and ammonia removers (zeolite/clinoptilolite) do, when each is genuinely useful versus unnecessary or harmful in a planted tank (phosphate removers starve plants; carbon/Purigen strip beneficial tannins), where they sit in the filter, and how to replace and regenerate them (including safe Purigen bleach regeneration).
- [DIY Aquarium Fertiliser: The Honest, No-Fear Guide to Mixing Your Own](https://www.aquacalc.uk/blog/diy-aquarium-fertiliser): A comprehensive, science-backed guide to making your own aquarium fertiliser from raw salts (KNO3, KH2PO4, K2SO4, CSM+B). Demystifies the chemistry, tackles the common safety fears, gives a worked recipe and a cost comparison against commercial all-in-ones, and links to the Make Your Own Fertiliser calculator.
- [Potassium buildup and toxicity in planted tanks: what the science says](https://www.aquacalc.uk/blog/potassium-buildup): Whether potassium 'builds up' to toxic levels in a planted aquarium — accumulation versus toxicity, cation antagonism, and why high potassium and nitrate readings are usually a symptom of stalled growth rather than its cause.
- [The ADA Super Jet Filter: a deep technical dive](https://www.aquacalc.uk/blog/ada-super-jet-filter): A technical deep-dive into the ADA Super Jet Filter: its IWAKI magnetic-drive pump, flow-versus-head behaviour, SUS304 stainless canister, Bio Rio media and lily-pipe flow dynamics, with a full specification table for every model.
- [Mobile and immobile nutrients: where plant deficiencies show up first](https://www.aquacalc.uk/blog/nutrient-mobility-in-plants): Mobile and immobile nutrients: what phloem mobility is, why mobile-nutrient deficiencies (N, P, K, Mg) show on old leaves while immobile ones (Fe, Ca, B, Mn) show on new growth, and why the rule is a useful first filter rather than a diagnosis in aquaria — where plants also feed through their leaves.
- [Aquarium plant nutrient deficiencies: a symptom guide](https://www.aquacalc.uk/blog/nutrient-deficiency-diagnosis): Aquarium plant nutrient deficiency diagnosis: a symptom-and-location guide built on nutrient mobility. Mobile nutrients (nitrogen, phosphorus, potassium, magnesium) show damage in old leaves; immobile nutrients (iron, calcium, sulphur, micros) in new leaves. Covers nitrogen yellowing, potassium pinholes, magnesium vs iron interveinal chlorosis, calcium distortion — and why to rule out low or unstable CO2 and excess light first, then dose a complete fertiliser rather than chase a single element.
- [Can your aquarium be stable if your tap water isn't?](https://www.aquacalc.uk/blog/aquarium-stability-tap-water): Can your aquarium be stable if your tap water isn't: a peer-reviewed, thought-provoking piece using a real UK water report (Essex & Suffolk Water, zone Z609) showing tap pH, GH, KH and nitrate all swing across a year — nitrate by nearly 7x. Argues that what stresses fish is the rate and magnitude of change, not a steady non-ideal value (gill acclimation takes days; Kwong/Kumai/Perry 2014; Fromm 1980); that the dramatic nitrate swing is toxicologically trivial once the NO3 vs NO3-N x4.43 unit slip is corrected (Camargo & Alonso 2006; Learmonth & Carvalho 2015; Monsees 2017); that a big water change is the real step-change disturbance; and that 'the mature tank buffers all variation' is mostly folklore (Vanderzwalmen 2022 shows substrate actively alters water). Honest that seasonal-tap-harms-fish is untested. Bottom line: consistent and gradual beats frozen and perfect.
- [Fish disease in the freshwater aquarium: lifecycles, medicines and myths](https://www.aquacalc.uk/blog/fish-disease-science): Fish disease in the freshwater aquarium: how the common diseases (ich, velvet, columnaris, fin rot, dropsy, fish TB) start and their lifecycles, whether off-the-shelf medications actually work, and where treatment advice is science versus folklore (including the raise-the-temperature-for-ich debate).
- [The gill: the most vulnerable organ in your aquarium](https://www.aquacalc.uk/blog/fish-gill-health): Why the gill is the most exposed organ in an aquarium: how suspended solids, ammonia, nitrite, low oxygen, metals and pathogens all damage the same thin tissue, why dissolved organic carbon is protective, and what practically protects gills.
- [The over-clean trap: why a sterile tank is not a healthy one](https://www.aquacalc.uk/blog/over-cleaning-aquarium): The over-clean trap: why a sterile aquarium is not a healthy one — how over-cleaning and sterilising strip the mature microbial community that suppresses opportunistic fish pathogens, why disinfection reduced survival in aquaculture trials, and how to clean for stability (rinse media in tank water, do not replace it all at once) rather than sterility.
- [Filter maturity: what a mature filter actually is, and why cleaning it sets you back](https://www.aquacalc.uk/blog/filter-maturity): The difference between a cycled filter and a mature one: biofilm structure, the r/K-selection microbial maturation framework from aquaculture, why over-cleaning and disinfection backfire, realistic timescales, and how to rinse media without resetting the community.
- [Does crystal-clear water actually mean healthy fish?](https://www.aquacalc.uk/blog/crystal-clear-water): Does crystal-clear water mean healthy fish? A science-backed look at why optical clarity is largely aesthetic: no study isolates clarity as a health variable, clear water can hide lethal invisible ammonia, suspended-solids harm only appears at loads far above tank norms, cloudy bacterial blooms signal microbial instability rather than directly poisoning fish, and tannin-tinted blackwater (dissolved organic carbon) is often physiologically protective. Thesis: chase stable, safe water, not transparency.
- [The case for tinted water: blackwater, tannins and fish health](https://www.aquacalc.uk/blog/blackwater-tannins): Explains why tint (refractory humic and fulvic compounds bacteria cannot eat) is chemically distinct from cloudiness (suspended bacteria feeding on labile organics), and sets out the peer-reviewed protective physiology of dissolved organic carbon at the fish gill — reduced diffusive sodium loss and sustained ion regulation in soft acidic water, metal binding underpinning the copper Biotic Ligand Model, and reduced respiratory stress at low pH — plus the honest limits: conditional on soft acidic water, source-specific, reversing at extreme acidity, and no substitute for husbandry. Includes practical botanical sources, the pH/KH relationship, the activated-carbon trade-off, and which species benefit.
- [The maths of overfeeding: what a gram of fish food does to your water](https://www.aquacalc.uk/blog/overfeeding-nitrogen-maths): The maths of overfeeding — a nitrogen mass balance of fish food: how much ammonia and nitrate a feeding produces, why uneaten food is worse, and how tank size and filtration change the outcome.
- [The calcium-to-magnesium ratio in planted tanks: does it really matter?](https://www.aquacalc.uk/blog/calcium-magnesium-ratio): Whether the calcium-to-magnesium ratio matters in a planted aquarium — the debunked soil-science origin of the '3:1 ideal', why sufficiency of each ion beats a fixed ratio, and practical advice for hard- and soft-water keepers.
- [Can you dose iron and phosphate together? What the chemistry says](https://www.aquacalc.uk/blog/iron-phosphate-dosing): Can you dose iron and phosphate together? Explains why FePO4 precipitation is real but defeated by chelation (stability constants vs Ksp), why the macro/micro separation rule is about concentrated stock bottles not the tank, and how all-in-one fertilisers keep iron and phosphate in one bottle (acidic concentrate, stronger chelate, lean formulation, excess chelator).
- [Measuring pH: how every method works, and where each one fails](https://www.aquacalc.uk/blog/measuring-ph): Measuring pH: a peer-reviewed guide to how each pH-measurement method works (glass electrode, better soft-water electrodes, ISFET, colorimetric/drop checker, spectrophotometric, and KH+conductivity inference), their real-world accuracy, and which suits hard, soft near-neutral or blackwater. Explains why residual liquid junction potential makes ~+/-0.1 pH the honest expectation in soft water and why low pH is the easy regime. Includes an embedded pH Method Finder picker.
- [Essential aquascaping tools: the minimum kit that actually matters](https://www.aquacalc.uk/blog/aquascaping-tools-guide): Which aquascaping tools are genuinely essential, sorted into four tiers — tweezers (including the length-vs-tank-depth rule), scissors, substrate spatulas, algae scrapers and water-change kit — plus what can be skipped or improvised.
- [Tissue culture vs potted aquarium plants: the real differences](https://www.aquacalc.uk/blog/tissue-culture-vs-potted-plants): Compares tissue-culture (in-vitro) and potted (rockwool net-pot) aquarium plants: how each is produced, pest and pesticide risk, cost per usable plant rather than per unit, size and establishment speed, melt, species availability, and which format suits carpets, large rosettes and epiphytes.
- [Does aquarium algae spread? The science of how it takes over](https://www.aquacalc.uk/blog/does-algae-spread): Explains whether aquarium algae — especially black beard algae (Compsopogon coeruleus) — spreads: yes, via water-borne monospores and fragments that raise propagule pressure, but establishment is gated by tank conditions and by biotic resistance from healthy plants, not contagion. Covers why BBA settles in high-flow zones and on old or stressed tissue, and the two levers (remove the source, fix the cause) that actually stop the spread.
- [Brown algae (diatoms) in a new aquarium](https://www.aquacalc.uk/blog/brown-algae-diatoms): silica-shelled algae forming a soft brown dust on glass, sand and leaves that wipes off easily. New tanks are silica-rich and low-competition, so diatoms bloom from about week 2 to week 8 then clear as the tank matures. Treatment is patience, wiping and siphoning, and grazers (otocinclus, nerite snails) once cycled — no chemicals needed. Distinct from slimy, musty cyanobacteria
- [Hair and thread algae: causes and control](https://www.aquacalc.uk/blog/hair-thread-algae): Hair and thread algae: what the common filamentous green algae (soft Oedogonium hair, silky Spirogyra thread, tough branched Cladophora) are, why they appear (light outrunning plant growth, unstable CO2, ammonia spikes), and how to clear them — manual removal, cutting light, fixing CO2 and feeding, spot-treating with H2O2 or glutaraldehyde, and clean-up crews. Grey-green antler-like staghorn is a red alga, treat as black beard algae.
- [Cyanobacteria (blue-green algae) in the aquarium](https://www.aquacalc.uk/blog/cyanobacteria): Cyanobacteria (blue-green algae, BGA): a photosynthetic bacterium, not an alga — slimy blue-green (or black/red) sheets that peel off in one piece with a musty geosmin smell. Triggers: poor flow and dead spots, accumulated organics, and often very low nitrate (many strains fix their own nitrogen). Beat it with manual removal, a 3-4 day blackout, better circulation and housekeeping, and a little steady nitrate; erythromycin works because it is a bacterium but risks harming the biofilter.
- [Why algae really happens in a planted tank](https://www.aquacalc.uk/blog/why-algae-happens): an evidence-weighted guide separating established science (phytoplankton prefer ammonium; plant-algae competition for nutrients and light; lab-proven macrophyte allelopathy) from hobby folklore (CO2 swings causing black beard algae; 'instability not nutrients'; cutting nitrogen to fight algae). Explains ammonia as the best-supported trigger and why healthy, fast-growing plants suppress algae. Companion to the Growing aquarium plants pillar
- [Why some plants need CO₂ and others don't](https://www.aquacalc.uk/blog/aquatic-plant-carbon-use): Why some plants need CO2 and others don't: the carbon-acquisition physiology behind the 'easy vs hard' plant divide. Carbon limitation of submerged photosynthesis (CO2 diffuses ~10,000x slower in water; diffusive boundary layer), bicarbonate use and carbon concentrating mechanisms (about half of freshwater angiosperms; documented in Vallisneria, Elodea, Egeria, Hydrilla, Potamogeton), the absence of bicarbonate use in mosses/liverworts/ferns, C4-like (Hydrilla) and CAM aquatic photosynthesis, and biogenic decalcification. Explains why CO2 injection is transformative for CO2-restricted species. Companion to the Growing aquarium plants pillar.
- [How long should the aquarium lights be on?](https://www.aquacalc.uk/blog/aquarium-photoperiod): How long should the aquarium lights be on: a guide to photoperiod and daily light integral (DLI) in planted tanks. Total daily light dose (intensity times hours) drives growth; light saturates and excess causes photoinhibition; there is no fixed 'plants stop after 6-8 hours' rule. Includes an evidence-based verdict on the siesta / split-photoperiod method for algae control (no controlled support). Companion to the Growing aquarium plants pillar.
- [Growing aquarium plants: the science that makes it make sense](https://www.aquacalc.uk/blog/growing-aquarium-plants): Growing aquarium plants: a peer-reviewed pillar guide that reframes planted-tank care around Liebig's limiting-factor model — growth is capped by the single scarcest resource. Covers light as a demand-setter (DLI, saturation), carbon as the usually-hidden limiter (10,000x slower diffusion, bicarbonate users vs CO2-restricted plants), diagnosing nutrient deficiencies by mobility, substrate CEC, flow and the leaf boundary layer, why new plants melt, and an honest, evidence-weighted section on why algae happens. Flags hobby lore (EI, Redfield, the siesta photoperiod, CO2-swings-cause-BBA) as practitioner experience, not established science. Links to deep-dive spokes.
- [Trimming aquarium plants: where the plant grows from decides every cut](https://www.aquacalc.uk/blog/trimming-aquarium-plants): Trimming aquarium plants: why "cut above a leaf node" only applies to stem plants, what a node and an axillary bud actually are, how apical dominance makes a topped stem branch, and how to trim rosettes, carpets, rhizome epiphytes, mosses, floaters and bulbs without damaging their single growing point - plus when a leaf is worth removing, based on which nutrients the plant can reclaim from it

## Other pages
- [Join / free membership](https://www.aquacalc.uk/join): why create a free AquaCalc account: back-in-stock alerts across 8 UK shops, saved shopping lists re-priced daily, a per-tank parameter log, a maintenance schedule with a weekly reminder, heat-wave warnings by postcode, saved favourites; passwordless email sign-in, no ads, no tracking, UK GDPR
- [Coming soon](https://www.aquacalc.uk/coming-soon.php): what we are writing next: upcoming guides and plant profiles with teaser copy and expected timing, generated live from the editorial schedule
- [Build your first planted aquarium](https://www.aquacalc.uk/build-your-first-aquarium.php): complete beginner roadmap, in order: siting and weight, choosing the tank, filter/heater/light, substrate and hardscape, planting, fishless cycling with an honest account of "silent"/planted cycling, first fish and the first three months
- [Planted tank guide](https://www.aquacalc.uk/guide.php): beginner overview
- [FAQ](https://www.aquacalc.uk/faq.php)
- [Resources directory](https://www.aquacalc.uk/resources.php): curated, UK-first, neutral, no affiliate links: planted-tank shops, filter/lighting/CO2 brands, fertilisers, substrate, communities and reference databases
- [UKAPS overview](https://www.aquacalc.uk/ukaps.php): the UK Aquatic Plant Society community
- [About AquaCalc](https://www.aquacalc.uk/about.php)
- [Disclaimer](https://www.aquacalc.uk/disclaimer.php): tool accuracy, limitations, no liability for livestock
- [AquaCalcBot](https://www.aquacalc.uk/bot.php): what our catalogue reader requests from the shops in the price comparison, how often, and how a shop owner has their listings removed

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