Cookie Policy
We have kept this genuinely short because there is genuinely not much to say. AquaCalc uses no advertising cookies, no tracking cookies and no third-party profiling.
Short version: We use no cookies for advertising or tracking. We use a strictly-necessary PHP session cookie on the feedback form (for CSRF security), to keep you signed in if you use an optional AquaCalc account, and to keep aquarium-shop customers logged in to the separate AquaCalc for Business portal. Browser localStorage stores your anonymous dashboard client ID — not a cookie, not personal data. Plausible Analytics operates without cookies entirely.
What is a cookie?
A cookie is a small text file stored on your device by a website. Cookies can be used for many purposes — from keeping you logged in, to tracking your behaviour across multiple websites for advertising purposes.
UK law (the Privacy and Electronic Communications Regulations — PECR — and UK GDPR) requires websites to tell you what cookies they use and, where required, to ask for your consent before setting them.
Cookies we use
Functional — sync client ID cookie (aqph_cid)
When you use the AquaCalc dashboard, or save inputs in a calculator so they sync across your devices, a randomly-generated anonymous client ID is created to link your browser to your saved tank profiles and tool inputs. This ID is stored in both your browser's localStorage and a cookie, so that your data is not lost if you clear your browser cache (which wipes localStorage but not cookies).
| Property | Value |
|---|---|
| Name | aqph_cid |
| Purpose | Keeps your anonymous profile ID intact if localStorage is cleared |
| Duration | 2 years |
| Third party? | No — set by our server only |
| Tracks you? | No — contains only a random anonymous identifier with no personal data |
| Consent required? | No — functional cookie required to prevent accidental loss of your saved profiles |
This cookie contains only the random client ID string. It cannot be used to identify you personally and is never shared with any third party. If you have never used the dashboard or saved any calculator inputs, this cookie is not set.
Strictly necessary — PHP session cookie (feedback form & Business portal login)
When you visit the feedback form, our server creates a temporary PHP session to:
- Generate and validate a security token (CSRF protection) that prevents automated form submissions
- Rate-limit submissions to prevent abuse
| Property | Value |
|---|---|
| Name | PHPSESSID |
| Purpose | Security (CSRF protection & rate limiting) |
| Duration | Session only — deleted when you close your browser |
| Third party? | No — set by our server only |
| Tracks you? | No — contains only a random session identifier |
| Consent required? | No — strictly necessary for security |
Under PECR, strictly necessary cookies do not require consent. This cookie is not used to identify you, track your behaviour, or store any personal data.
Account sign-in (your AquaCalc account & Business portal). The same strictly-necessary PHP session cookie also helps keep you signed in to your optional AquaCalc account (used across the tools, dashboard and comments) and to the separate AquaCalc for Business portal for shops. Sign-in is passwordless (a one-time email link), and the session cookie holds only a temporary session identifier so the server knows you are logged in for that visit; it stores no personal data itself.
Functional — account sign-in cookie (aq_acct)
If you sign in to your optional AquaCalc account (to manage your newsletter and heat-alert subscriptions, and have your comments recognised across devices), we set a cookie so you stay signed in on that device without clicking an email link every visit. Sign-in is passwordless. Using the tools, dashboard and articles needs no account at all.
| Property | Value |
|---|---|
| Name | aq_acct |
| Purpose | Keeps you signed in to your account across visits |
| Duration | 90 days (renews while you stay active) |
| Third party? | No — set by our server only |
| Tracks you? | No — a signed token identifying your account only; no browsing or advertising data |
| Consent required? | No — functional cookie required to keep you signed in to a service you asked for |
Account data (your email, name and subscription settings) is described in our Privacy Policy.
What we do not use
| Type | Used? | Notes |
|---|---|---|
| Advertising cookies | ✕ No | We run no advertising of any kind |
| Tracking / analytics cookies | ✕ No | Plausible Analytics is cookieless — see below |
| Social media cookies | ✕ No | No social sharing buttons or embeds |
| Profiling cookies | ✕ No | We build no user profiles |
| Cross-site tracking | ✕ No | We do not track you across other websites |
| Advertising / tracking login cookies | ✕ No | The tools, dashboard and articles need no login. The optional account keeps you signed in with a functional first-party cookie (aq_acct, above) that holds only a signed account token — never advertising or cross-site data |
| Third-party marketing cookies | ✕ No | We do not use Mailchimp, SendGrid or any email platform that sets cookies |
Browser localStorage (not a cookie)
AquaCalc uses your browser's localStorage to store your anonymous client ID and remember which dashboard profile was last active. localStorage is not a cookie — it cannot be read by any other website and is entirely under your control.
If you clear your browser's localStorage for aquacalc.uk, the dashboard will automatically restore your client ID from the aqph_cid cookie (described above), so your saved profiles are not lost. If you clear both localStorage and cookies, the client ID is gone and an anonymous profile can no longer be accessed. Creating an optional My Tank account avoids this — signing in restores your tanks on any device.
Newsletter subscription — how your data travels
When you subscribe to the AquaCalc newsletter, your name and email address are stored on our server and used only to send you emails directly from our own mail server ([email protected]). We do not use any third-party email marketing platform that might set cookies in your browser or track when you open emails. For full details of what subscriber data we hold and how it is protected, see our Privacy Policy.
Plausible Analytics — cookieless
We use Plausible Analytics to understand how many people visit AquaCalc and which pages are most popular. Unlike most analytics tools, Plausible sets no cookies whatsoever. It operates using a daily hash of your IP address and user agent to count unique visitors — a hash that cannot be used to identify you and is discarded after 24 hours.
The Plausible script and event collection endpoint are proxied through our own domain (aquacalc.uk), so no request is made directly to plausible.io from your browser. Plausible is fully compliant with UK GDPR, EU GDPR and PECR. No consent banner is required because it collects no personal data and sets no cookies. You can verify this at plausible.io/data-policy.
Third-party scripts
The charting library used on the dashboard, parameter log and share pages is served directly from AquaCalc, so no third-party CDN is contacted to display charts. The only remaining third-party request is optional: when you set up two-factor login in the dashboard, a small QR-code library is loaded on demand from the jsDelivr CDN (cdn.jsdelivr.net). This does not set any cookies, though jsDelivr may log your IP address as part of normal CDN operation. See jsDelivr's privacy policy for details.
Managing cookies
You can control and delete cookies through your browser settings. Deleting the PHP session cookie will not affect your use of the dashboard or your newsletter subscription — it is used only for the feedback form, optional My Tank and Business portal sign-in, and security — and contains no personal data (deleting it while signed in will simply log you out). Instructions for managing cookies:
Changes to this policy
If we ever introduce new cookies or change how we use existing ones, we will update this page and revise the date at the top. Given the privacy-first design of AquaCalc, we do not anticipate significant changes.
Who operates this website
AquaCalc is built, managed and owned by SaneChoice, Moulsham Mill, Parkway, Chelmsford, CM2 7PX, United Kingdom.
Contact & complaints
For any questions about our use of cookies, please use the feedback form. You also have the right to complain to the Information Commissioner's Office (ICO) at ico.org.uk if you believe we are handling cookies unlawfully.