Fish Tank Tracker

Fish Tank Tracker is the lab notebook your aquarium deserves: log a full water test in seconds, watch the trends, and never miss another water change. Built for reef, FOWLR, saltwater, freshwater and brackish tanks — and built to work entirely offline, with no account and no subscription. TEN PARAMETERS, LOGGED IN SECONDS • Temperature, salinity (ppt or specific gravity), pH, ammonia, nitrite, nitrate, alkalinity, calcium, magnesium and phosphate • Quick mode for the everyday basics, Full Test for lab day • Optimal ranges and your last reading shown while you type, notes on every test • A reading that looks like a typo (42 for 420) is questioned before it's saved • Type phosphorus in ppb straight from a Hanna ULR checker • Type alkalinity in dKH, meq/L or ppm, as your test kit reads it • Set your own target range for any parameter, tank by tank • Log a test you took yesterday, or fix one you mistyped • Share any test as text, for a second opinion on the forums CHARTS THAT TELL THE STORY • Every parameter charted against its optimal band, over 30 days, 90 days, a year or all time • Tap a chart for any reading, with your water changes marked on it • Color-coded status on the dashboard: optimal, acceptable or critical at a glance • Every reading shows how it moved since your last test • Spot a slow drift weeks before it becomes a problem LIVESTOCK JOURNAL • Fish, corals and invertebrates with species names and photos • Purchase dates, quantity, cost and health status EQUIPMENT & MAINTENANCE • An inventory of lights, pumps, heaters, skimmers and more • Recurring tasks per piece of equipment: clean the skimmer cup, swap filter floss, wipe the lens • A reminder notification when a task comes due, plus a weekly test-day reminder on the day and time you choose WATER CHANGES & DOSING • Log water changes by percent or volume, even from earlier days, and fix them later • Dosing calculator for alkalinity, calcium and magnesium — pick your product, get millilitres for your exact water volume • Big corrections are split into daily doses, never faster than the product's label allows • Dose straight from a test: the calculator starts from your latest reading and your own target • Water change calculator: how much salt to mix, and how far nitrate and phosphate will drop YOURS, OFFLINE • Everything is stored in a local database on your device • Free backup and restore: save everything to Files or Drive, and move it to a new phone • No account, no login, no cloud, no tracking — and no ads • Gallons or liters for each tank, °F or °C FREE AND PRO The free version is a complete toolkit for one tank: all ten parameters with charts, a month of history, five livestock entries, and every equipment, maintenance and dosing tool. Pro is a single one-time purchase — never a subscription — and unlocks unlimited tanks, unlimited history, unlimited livestock, trend analysis with stability scores, and CSV export. Whether you are cycling your first ten-gallon aquarium or dialing in a mature reef tank, Fish Tank Tracker keeps the numbers so you can enjoy the fish.