Parameter log
Record water test results whenever you like, for as many tanks as you need. View each parameter as a graph over time.
Data is saved to this browser. Use Export CSV in the Log tab as a backup. To move data to another device: export here, then import on the other device after selecting the right aquarium.
Tracking water quality over time
A single test result tells you where your tank is right now. A series of results tells you whether it is improving, declining, or stable — and that trend is where the real information is. The Parameter Log records any measurement with a timestamp and an optional note, then plots them as time-series graphs so you can see patterns that are invisible in individual readings.
Each aquarium gets its own profile. You can log as many parameters as you test, as frequently or infrequently as you like — the log handles irregular intervals and will plot everything cleanly regardless of how often you test.
Add a note on every reading
The note field is optional but valuable. Recording what changed alongside the measurement — a water change, a dose of fertiliser, a new CO₂ regulator setting — turns a data point into context. When something goes wrong, or unexpectedly right, your notes tell you why.
Macronutrients, micros and water chemistry
For a planted tank, the parameters most worth logging regularly are the ones you are actively managing. Nitrate (NO₃⁻) and phosphate (PO₄³⁻) drift with plant demand and water change frequency — logging them before and after water changes quickly reveals your actual consumption rate. Potassium (K⁺) is less commonly tested but relevant if you are dosing a two-part or EI regime. KH and GH matter if you are mixing RO water or your tap supply fluctuates seasonally.
For micros, iron (Fe) is the most commonly tested — most planted tank keepers aim for 0.05–0.1 mg/L during the photoperiod. Because iron is rapidly oxidised and taken up by plants, a reading taken at lights-off will be significantly lower than one taken at lights-on. Note the time of day on every iron test to make comparisons meaningful.
Micronutrient units
The log defaults micros (Fe, Mn, B, Zn, Cu, Mo) to µg/L — micrograms per litre. Some test kits, particularly older API and Sera kits, display results in mg/L. If your kit reads in mg/L, change the unit field on each reading to match — the log stores whatever unit you enter alongside the value.
Managing more than one aquarium
Create a separate aquarium entry for each tank using the + New tank button. Data is kept entirely separate between tanks — charts and logs only show readings for the currently selected tank. You can switch between tanks at any time using the selector at the top of the page.
If you are moving data to a new device or browser, export each tank's CSV separately and import them one at a time, switching to the correct tank before each import.
Use the AquaCalc dashboard to manage CO₂ targets, dose fertilisers, and mix RO water alongside your logged readings — all tools in one place.