manfred · the answers
Frequently asked questions
Short answers to the questions reefnotes users ask most often. If yours isn't here, the privacy policy or a quick mail to feedback@reefnotes.com will sort it.
- Is reefnotes free?
- Yes — reefnotes is free to use and ad-free. Your logbook stays yours; we don't sell data or run third-party analytics. Visits are counted with our own self-hosted statistics, without cookies.
- Does reefnotes work for reef tanks, planted tanks and freshwater?
- Yes. You pick the tank type when you create an aquarium — freshwater/planted, marine or reef — and the matching parameters and target bands follow. reefnotes grew up on planted freshwater tanks, so that's where the dosing logic has seen the most real data.
- What does reefnotes track?
- Water tests (NO3, PO4, KH, Ca, Mg, pH, NH4, NO2, SiO2, Fe and more), water changes, dosing events, and recurring maintenance tasks. The trend charts mark water changes and show a short forecast, so you can see the slow drift between measurements.
- Where is my data stored?
- On reefnotes servers in Germany. No third-party analytics, no advertising trackers, no data resale; visits are counted by our own self-hosted, anonymous statistics without cookies. When you delete your account, everything you logged is removed by default; if you opt in at signup you can let your readings be kept fully anonymised (no name, no email, no tank names, no notes) so the trends and forecasts can keep getting better. See the privacy policy at reefnotes.com/en/privacy for the full list of what's logged and why.
- Do I need to enter values in mg/L or ppm?
- reefnotes uses mg/L by default for nitrogenous compounds, phosphate and most micros. For freshwater hobbyists who think in ppm, the two are interchangeable for these parameters (1 mg/L ≈ 1 ppm in dilute aquarium water).
- Does reefnotes suggest doses?
- Yes. Dose recommendations are tuned to your water-change cadence and the trend slope of the parameter you're correcting — so when NO3 is creeping up between water changes, you get a suggestion that closes the gap without overshooting.
- Is reefnotes available in German?
- Yes — the entire UI is available in English and German. You can switch in the pill nav at any time and the choice is remembered across sessions.
- Can I use reefnotes on my phone?
- Yes. reefnotes is a responsive web app that runs in any modern mobile browser. You can also add it to your home screen on iOS and Android via the browser's 'install / add to home screen' action.
- How do I rename a tank or change its volume?
- Open the tank and tap the pencil next to its name. Name, setup date, volume (with the volume calculator), location, water type and CO₂ injection are all editable there. The same form lives under “Setup → Tank details” at the bottom of the page.