ReefLog: Water Parameters

Your reef tank's chemistry tells a story. ReefLog helps you read it.

Track alkalinity, calcium, magnesium, and 10 more parameters with beautiful trend graphs, target range indicators, and instant status dashboards. Built exclusively for saltwater reef aquariums -- not freshwater, not ponds, not general "aquarium management."

No subscription. No account required. No ads. Pay once, own it forever.

--- LOG WATER TESTS IN SECONDS ---

Tap, enter your numbers, done. ReefLog is designed for speed because you're logging parameters at your tank, not sitting at a desk. Every parameter a reef keeper tracks is built in with the correct units:

- Alkalinity (dKH, meq/L, ppm CaCO3)
- Calcium (ppm)
- Magnesium (ppm)
- Salinity (ppt, SG, PSU)
- pH
- Temperature (F / C)
- Nitrate (ppm)
- Phosphate (ppm, ppb)
- Ammonia, Nitrite, Potassium, Strontium, Iodine

--- SEE TRENDS BEFORE PROBLEMS START ---

Beautiful trend graphs show your parameter history with ideal target ranges highlighted. See at a glance whether your alkalinity is drifting, whether your calcium consumption is increasing, or whether that new dosing schedule is actually working. Compare multiple parameters on a single chart to spot correlations.

Spot problems before your coral does.

--- DASHBOARD WITH STATUS AT A GLANCE ---

Every parameter displays a color-coded status indicator -- green when in range, yellow when drifting, red when out of range. Mini sparkline graphs on every card show recent trends without opening a single chart. Know your tank's health the moment you open the app.

--- TRACK EVERY TANK YOU RUN ---

Display tank, frag tank, quarantine tank -- each one gets its own dashboard, its own history, its own target ranges, its own trend lines. Support for up to 10 tanks. Switch between them instantly with a single tap.

--- YOUR DATA, YOUR DEVICE ---

No account required. No login screens. No server dependency. Your data lives on your device. You will never lose years of parameter history because of a server outage or a broken password reset.

Export to CSV anytime -- your data is always yours. Perfect for hobbyists who also maintain spreadsheets or want to run their own analysis.

--- BUILT BY A REEFER, FOR REEFERS ---

ReefLog speaks your language. Alk in dKH or meq/L. Calcium in ppm. Salinity in ppt or specific gravity. Target ranges based on proven reef chemistry, not generic aquarium values. Customizable ranges per tank because your SPS-dominant display has different targets than your quarantine tank.

Set test reminders so you never miss a weekly alk check. Dark mode that looks great at 11pm when you're doing your evening tank check.

--- WHAT MAKES REEFLOG DIFFERENT ---

- Reef-specific from day one (not a general aquarium app)
- Modern, native iOS design (not a 2012 UI)
- Local-first data storage (no account, no data loss)
- Focused on parameters (does one thing exceptionally well)
- One-time purchase (no subscription fatigue)
- Active developer who actually responds to feedback

--- DESIGNED FOR SERIOUS REEF KEEPERS ---

If you're testing alk, calcium, and magnesium every week -- and then writing the numbers on a sticky note or burying them in a spreadsheet -- you already know you need a better system.

ReefLog is the tool you've been looking for.

One-time purchase. No subscription. No ads. No account required.
Your reef deserves better than a spreadsheet.