Reefkeel reads your alk, cal, and mag over time, catches the drift, and hands you the exact mL/day to dose back to target. A marine instrument for manual-dosing reefers — not another aquarium logbook.
A logbook tells you what happened. An instrument tells you what to do.
Most reef apps are notebooks — you type the numbers in and they just sit there. By the time a swing shows up in the data, the coral is already paling. Reefkeel reads the trend and gives you the dose before it gets there.
Log a couple of tests and Reefkeel computes how fast your reef burns alk, cal, and mag — then outputs a personalized maintenance dose in mL/day of the additive you actually use. No black box: it shows the drift it caught and the math behind the number.
“Alk down 0.4 dKH over 3 days.” It flags the slide while there's still time to correct it.
“Bump to 12 mL/day to hold 8.4.” Specific to your volume, your additive, your uptake.
Built on the published dosing strengths of common reef additives — pick a preset or enter your own.
Free does the whole core loop — log, chart, calculate. Pro unlocks the depth: auto-dosing from your own data, multiple tanks, and ICP trending.
Your headline parameter as a single live trend line through a shaded target band. Dialed in? The line is flat. That's the whole idea.
A personalized daily maintenance dose, computed from your tank's measured uptake — recalculated as your reef changes.
Current value, target, tank volume, additive → mL/day and doses-per-bottle. A clean single-shot calc, free forever.
Turn siloed single-shot ICP results into a longitudinal trace-element trend. See which elements are climbing or crashing across every test — not just the latest PDF.
Each system keeps its own log, charts, and doses. Switch context in a tap.
A quiet reminder when it's time to test again — the cheapest way to keep the cadence.
No account, no cloud, no tracking. Your logs live on your phone and work with the router unplugged.
Punch in your reading — alk, cal, mag, and the rest. Reef Titration numbers in, done in seconds.
The reading lands on your trend, against a shaded target band. In range, or drifting — you see it at a glance.
Drift caught, Reefkeel computes the mL/day to bring it back. Set it, and hold the line.
Every parameter gets a clean trend line with its target band drawn right on the chart — so a swing is obvious the moment it starts, not three tests later. No rainbow spaghetti, no buried tables. Just the line, and where it should be.
The whole core loop — logging, charts, and the dosing calculator — is free forever. Pro is for reefers running it daily across real systems.
Reefkeel is on the App Store now. Free to start — Pro unlocks auto-dosing, multiple tanks, ICP trends and CSV export.
Download on the App Store →