Stop juggling spreadsheets and sticky notes. Reef Ledger is the dedicated logbook serious saltwater and reef keepers have been asking for, built to run entirely on your iPhone. Track alkalinity, calcium, magnesium, nitrate, phosphate, salinity and anything else you measure with a fully customizable parameter library, then watch trends emerge on clean charts so you catch a swing before it becomes a crash. When it is time to dose, let the built-in calculator do the math: enter your target shift and tank volume and get the exact milliliters of two-part, kalkwasser or magnesium to add. Plan water changes with real salinity math, and set a maintenance schedule that fires proper time-sensitive notifications so testing and dosing never slip again. Everything stays on your device. No account, no sign-up, no data collection, just a fast and focused tool. Pay once and own it. An optional in-app upgrade unlocks multi-tank profiles and CSV export for your records. For a hobby where a single tank holds hundreds of dollars in coral and livestock, one prevented crash pays for this app many times over.
