TankLog: Aquascape
Fish Tank Log & Reminders
Free · In‑App Purchases · Designed for iPad. Not verified for macOS.
Free. Local. Yours. Now with a Large text size, and made for iPhone Duo.
Built by an aquascaper, for aquascapers.
Free. Local. Yours. TankLog is a free freshwater aquarium journal for planted tank and shrimp hobbyists. No login required. No subscription. It works fully offline, and everything stays on your device.
Built for the people who track CO₂ levels, obsess over KH and GH for their neocaridina colony, and want to know when their nitrates started creeping up. Not a generic fish app trying to cover everything.
WATER TESTING & PARAMETER TRENDS
Log pH, ammonia, nitrite, nitrate, KH, GH, phosphate (PO₄), TDS and temperature. Every reading is graded instantly against your own target ranges, and Parameter Trends charts every test so you can spot slow pH drifts, creeping nitrates or KH swings before they affect your plants or livestock.
CO₂ ESTIMATION
TankLog calculates dissolved CO₂ from your pH and KH and shows it as a color-coded zone: very low, low, ideal, high or at risk. Essential for high-tech planted tanks.
CARE SCHEDULES & ACTIVITY CALENDAR
Schedule water tests, water changes, filter cleans, dosing, feeding and more. Get reminders when tasks are due, see overdue items on your dashboard, and browse your whole care history and upcoming dates in the Activity Calendar.
DOSING, WATER CHANGES, FEEDING & CLEANING
Log every fertilizer, supplement and treatment with product, amount and date. Log water changes, feedings with species tags, and cleaning tasks, each with its own schedules and history.
ACHIEVEMENTS
Earn badges for consistent testing, on-time care and great water quality. Tap any badge to see how you earned it.
TANK NOTES
Jot down anything that isn't a log, like a tap water test or a new plant on the way. Notes show up in your Activity Calendar.
SIRI & SHORTCUTS
Say "Log a feeding in TankLog" and TankLog opens the right form, ready to fill in. Or put your own shortcut on the Action button.
EQUIPMENT, LIVESTOCK & PLANTS
Record your lighting, filtration, CO₂ system, heater and pumps. Log fish, invertebrates and plants (with scientific plant names), plus dates and notes.
MULTIPLE TANKS
Manage up to 3 tanks for free, each with its own parameters, schedules, livestock and history. Need more? Up to 10 Tanks is an optional one-time upgrade, with no subscription.
CLOUD SYNC (OPTIONAL)
Use TankLog on more than one device, or want a backup? Cloud Sync is an optional one-time upgrade, with no subscription, that keeps your tanks in your own private iCloud. A lost or new phone doesn't mean lost logs, and every iPhone and iPad signed in to your Apple Account stays the same. There's no account to create. TankLog can't see your synced data, and it's never sold, shared or used to market to you. Turn it off, or delete it from iCloud, whenever you choose.
YOUR DATA, YOUR WAY
Export your complete tank history as a file anytime and import it on any device. No account needed. Your data is yours, always.
No AI gimmick. No subscription. Every tracking feature free, forever. Just a well-built, honest tool from someone who loves this hobby as much as you do.
Metric and imperial units · 12h and 24h time · Light and dark mode · iPhone and iPad
Ratings & Reviews
NEW: TEXT SIZE
Bigger text, icons and buttons, all through the app. Open Settings, find Text Size and pick Large. Every screen was laid out again for it, down to the iPhone SE and in all seven languages, so nothing gets cut off or squeezed. It applies to all your tanks, and Default stays the size you know.
MADE FOR iPHONE DUO
TankLog now fills the whole inner screen on iPhone Duo. On the closed screen, and on the open screen held sideways, the tabs move into the side column by the camera, down where your thumb is, with the aqua wave on the open tab. Fold or unfold and the layout follows right away. Built for iOS 27.
DELETE A TANK FROM SETTINGS
You can now delete a tank in Settings under Data, right next to its Export button. Wherever you delete a tank from, TankLog asks a second time and says what will be erased. If you use Cloud Sync, it also tells you the tank goes from all your devices.
FIXES & POLISH
• Tab labels and icons are a little bigger on iPhone, and when the tabs don't all fit, the bar scrolls sideways instead of shrinking them
• Exporting a backup saves just the backup file, without an extra text.txt beside it in Files
• Cards, banners and page titles that ran over on smaller iPhones in German, French, Spanish, Italian or Portuguese now fit
• More labels in your language: the last reading on test tiles, tank age, and Next due in the Activity Calendar
Free. No login required. No subscription.
The developer, John Katez, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Linked to You
The following data may be collected and linked to your identity:
- Contact Info
- User Content
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- John Katez
- Size
- 3.8 MB
- Category
- Utilities
- Compatibility
Requires iOS 15.0 or later.
- iPhone
Requires iOS 15.0 or later. - iPad
Requires iPadOS 15.0 or later. - iPod touch
Requires iOS 15.0 or later. - Mac
Requires macOS 12.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 6 more
- English, Dutch, French, German, Italian, Portuguese, Spanish
- Age Rating
4+
- 4+
- In-App Purchases
Yes
- Up to 10 Tanks $3.99
- Cloud Sync $3.99
- Copyright
- © 2026 TankLog: Aquascape
