Stablereef: Reef Tank Tracker
Sloth Lab Inc. Utilities iPhoneiPadiPod touch
Stablereef: Reef Tank Tracker is a free Utilities app for iPhone and iPad by Sloth Lab Inc. Requires iOS 15.0. Updated October 20, 2026.
- Price
- Free
- on the App Store
- Size
- 31 MB
- Age 4+
- Updated
- Oct 20
- 2026 · v1.2.7
Screenshots
About Stablereef: Reef Tank Tracker
Stablereef is a fast reef tank tracker and water test log for saltwater aquariums. Log a full test in one quick session, catch a rapid Alk swing on the spot, and enter the units your test kit shows. Unlimited logging, CSV import and export — no account, no cloud, and no paywall in your core loop. LOG A FULL WATER TEST IN ONE SESSION Tap "Log a test session" and move through every parameter with a big number pad. Each step shows your last reading, only a rapid change stops you, and the rest lands in one summary where you can undo any single reading. Logging just one value? Tap its card and your last value is prefilled. Pin the parameters you test most and hide the ones you don't. No spreadsheet. THE ANTI-SWING WARNING Corals don't crash on a number; they crash on the swing. When you save a reading, Stablereef compares it to your last value — allowing for the time since that test — and flags a rapid change, like "Alk +1.3 dKH rapid change." Out-of-range readings are flagged too, using safe ranges re-checked against published reef guidance. You catch the risky move while you're still at the tank. (Reference only — bands are tunable and husbandry calls are yours.) ENTER THE NUMBER YOUR TEST KIT SHOWS Track Alkalinity, Calcium, Magnesium, Nitrate, Phosphate, Salinity, pH and Temperature — plus Ammonia, Nitrite and Silicate when you need them — in the units your kit actually reads: dKH, meq/L or ppm (as CaCO3) for alkalinity; ppm PO4 or ppb P for phosphate (ppb P is what a Hanna HI736 shows); °C or °F; ppt or specific gravity. No converting in your head. CYCLING A NEW SALTWATER TANK? Turn on "This tank is still cycling" and Ammonia and Nitrite move to the front. While the tank cycles, high ammonia and nitrite readings get a calm "this is expected" note instead of an alarm, and Stablereef tells you when your readings suggest the cycle looks done. SWITCHING APPS? BRING YOUR REEF LOG WITH YOU Moving from another aquarium app or a spreadsheet? Import your history from any CSV, right from the first screen: automatic column detection, unit conversion (dKH, meq/L or ppm alkalinity; ppm or ppb phosphate; °F/°C; SG/ppt), a prompt when a column's unit is unclear, a preview before anything is written, and a clear report of exactly what came in. Import is free. TRENDS, NOT JUST NUMBERS 7 / 30 / 90-day graphs with a shaded stability band let you separate real drift from noise and act before a small slip becomes a tank crash. YOUR DATA IS YOURS • CSV & JSON export, anytime — never behind a paywall • Automatic local backups • Works 100% offline — no account, no cloud, no sign-up Want your years of history out? One tap. We don't hold your data hostage. REMINDERS Local notifications for dosing and testing keep you on schedule on the days you'd otherwise forget. LOG AS OFTEN AS YOU TEST Unlimited logging, anti-swing warnings, trends, reminders, import and export are free. No subscription, no monthly cap on readings, and no paywall in the middle of your core loop — ever. THE "LESS" PHILOSOPHY No livestock encyclopedia. No marketplace. No social feed. Stablereef does one thing — protect your reef tank's stability — and aims to do it better than apps juggling ten. PRIVACY No account. No cloud. No ads, no cross-app tracking. Your reef data stays on your device — the only thing we collect is anonymous usage counts, with no account, no personal data and no IP address, and you can switch that off in Settings. WHO IT'S FOR Reef keepers who want a focused saltwater aquarium log instead of a do-everything app: an alkalinity tracker that flags swings, a water test log that matches your test kit, and a simple way to track ammonia and nitrite while a new tank cycles. If you keep a spreadsheet today, we built this for you. Reference tool only — not veterinary or husbandry advice. Stability bands are general references; care decisions are the keeper's responsibility. From Sloth Lab Inc.
What’s new
Version 1.2.7 · Updated October 20, 2026
Stablereef 1.2.7 — under-the-hood update. • Small improvements to anonymous usage reporting, so we can see what's working and keep improving the app • No changes to your tanks, readings, or backups Thanks to everyone logging with us — keep the feedback coming from Data → About → Send feedback.
App privacy
The developer, Sloth Lab Inc., reported these privacy practices to Apple.
Data Not Linked to You
The following data, which may be collected but is not linked to your identity, may be used for the following purposes:
- Usage Data: Product Interaction
Used for: Analytics
Alternatives to Stablereef: Reef Tank Tracker
Looking for apps like Stablereef: Reef Tank Tracker? Here are 6 similar apps on the App Store. The highest rated is ABS Admin: Audiobookshelf (5.0/5), and all 6 are free to download.
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ABS Admin: Audiobookshelf
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StableBit Cloud Notifications
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Store Buddy - Shopping List
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ReefMate: Aquarium Tracker&Log
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Fish Tank Log
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Reef Buddy: Reef Tank Tracker
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| App | Rating | Price | Last updated | Compare |
|---|---|---|---|---|
| Stablereef: Reef Tank Tracker | – | Free | October 20, 2026 | |
| ABS Admin: Audiobookshelf | 5.0 / 5 (1) | Free | Oct 21, 2026 | Compare |
| StableBit Cloud Notifications | – | Free | Jul 7, 2026 | Compare |
| Store Buddy - Shopping List | 4.7 / 5 (78) | Free | Aug 18, 2026 | Compare |
| ReefMate: Aquarium Tracker&Log | – | Free | Oct 20, 2026 | Compare |
| Fish Tank Log | 5.0 / 5 (6) | Free | Apr 14, 2026 | Compare |
| Reef Buddy: Reef Tank Tracker | 3.9 / 5 (20) | Free | Oct 17, 2026 | Compare |