Tank Journal: Water Test Log

Tank Journal is a log for your aquarium water tests. Write down what you tested, see at a glance which values are out of range, and follow how each one changes over time.

WATER TESTS
• Freshwater: temperature, pH, ammonia, nitrite, nitrate, GH, KH and phosphate
• Saltwater: temperature, salinity, pH, KH, ammonia, nitrite, nitrate, phosphate, calcium and magnesium
• Fill in only what you tested, for today or an earlier day
• Add a note to any test

TARGETS AND TRENDS
• Each parameter starts with a common target range, and you can set your own for every tank
• Values above or below the target are marked High or Low
• A chart for each parameter shows your tests over time, with the target range behind them

SPECIES
• Add the fish, plants, shrimp and snails in each tank from a built-in list, by common or scientific name

WATER CHANGES
• Mark a water change with one tap and see when you did the last one

REMINDERS
• Get a reminder when the next water test or water change is due, every 3, 7, 14 or 30 days for each tank

IMPORT FROM AQUAREKA (BETA)
• Open an Aquareka export file (JSON) from Settings, with "Open with", or from the share menu of another app
• Import is new. If a file doesn't open, email it to [email protected] and we'll look at it.
• See what will come in before anything is saved
• Tanks, species and water tests are imported. Importing the same file again adds only what is new.
• The export doesn't include photos or how many of each species you keep, so those aren't imported

YOUR DATA
• Works offline and needs no account
• Your tanks and tests are saved on your phone and never sent to us
• Export every water test as a CSV spreadsheet, or a full copy as a JSON file
• Litres or US gallons, °C or °F, light or dark theme

FREE AND PRO
• Free: two tanks with everything in them, every tank you import from Aquareka, import and export, and charts of the last 90 days
• Tank Journal Pro adds more tanks, charts of your whole history and more than 3 reminders, as a yearly subscription or a one-time purchase
• If you bring your tanks from Aquareka, the one-time purchase costs less until 31 December 2026
• Nothing you already saved is ever locked

Tank Journal is an independent app. It is not affiliated with or endorsed by Aquareka.