TankDiary vs ReefNote

Know when your new tank is safe for fish — TankDiary reads your ammonia, nitrite and nitrate tests and names the cycle stage you're in. Log a water test by tapping the color that matches your test tube. No account, no cloud, nothing leaves your phone. TRACK WHAT MATTERS Log temperature, pH, ammonia, nitrite, nitrate, GH, KH, TDS and more in one quick sheet. Color-coded safe ranges tell you at a glance if something's drifting. Interactive charts show trends over weeks or years — with the safe zone drawn right on the graph and touch-to-read values on every point. KNOW WHEN SOMETHING'S WRONG The home screen flags out-of-range parameters and overdue maintenance across all your tanks the moment you open the app — no drilling in required. NEVER MISS A WATER CHANGE Set schedules for water changes, filter cleans, dosing and trimming, with reliable local reminders at the time you choose. The built-in water change calculator tells you how much to pull, how much conditioner to add, and — the part nobody else answers — what the change will actually do to your nitrate, including the floor set by nitrate in your own tap water. YOUR WHOLE TANK, REMEMBERED Livestock list with photos — fish, inverts, plants — searchable by species. A photo journal for milestones, rescapes and diary notes, with full-screen pinch-to-zoom. Everything works offline. SPEAKS YOUR LANGUAGE Fully translated into German, Japanese and Brazilian Portuguese, with the terms hobbyists actually use. Units follow your region and can be changed anytime. HONEST PRICING Free forever: 1 tank, working reminders, 30 days of history, the full cycle tracker, the color chart and the calculator. TankDiary Pro unlocks unlimited tanks and full history as a one-time purchase — pay once, own it forever. There's a cheap yearly option too, but we think you'll prefer to just own it. No account. No cloud lock-in. No selling your data — there's nothing to sell; it never leaves your device. Made by a hobbyist who got tired of spreadsheet water logs. Privacy Policy: https://tankdiary.com/privacy.html Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/

ReefNote keeps your aquarium on track: log every water parameter, flag anything out of range, and keep dosing and maintenance on schedule. Testing is fast. Pick a parameter, tap the value on a big pad with the right unit (dKH, ppm, SG), and save. Each parameter remembers its last value, so a routine round of tests takes seconds. WHAT YOU GET - Parameter log with target ranges: reef and freshwater presets you can edit per tank, with out-of-range flags the moment you save - Trend charts: every parameter over 30 days, 90 days, or a year, with your target band drawn behind the line and each point coloured by its flag - Dosing and water changes: repeat schedules with clear overdue and due-today states, one tap to mark done - Livestock registry: fish, coral, and inverts with photos, added dates, and notes - Maintenance reminders: a per-task reminder so nothing slips - Tank journal: one timeline that mixes your tests, doses, and events - Tank report: a shareable PDF of parameters versus targets, livestock, and schedule, plus a CSV of every reading (Pro) REEF OR FRESHWATER Set the tank type and ReefNote starts with common target bands for each parameter, then lets you tune every band to the numbers you keep. FREE AND PRO Free includes one tank and 30 tests, with target ranges, trends, the schedule, and the livestock registry. Pro unlocks unlimited tanks, unlimited test history, and the PDF and CSV exports. PRIVATE BY DESIGN Everything stays on your iPhone. No account, no cloud, no tracking. SUBSCRIPTION DETAILS ReefNote Pro is available as a monthly or yearly subscription, or as a one time lifetime purchase. The current price is shown in the app and on this page before you buy. Payment is charged to your Apple Account at confirmation of purchase. Subscriptions renew automatically until cancelled. Manage or cancel anytime in Settings > Apple Account > Subscriptions; cancellation takes effect at the end of the current period. Terms of Use (Apple Standard EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/