Aquarium Calculator & Tools

Aquarium Calculator puts the everyday numbers of fishkeeping in one simple app: how much water your tank holds, how much to change, and how much product to add according to its label.

TANK VOLUME
• Rectangle, cylinder, bowfront, corner (quarter circle) and hexagon tanks
• Enter centimetres or inches and switch any time
• Subtract the empty space at the top, the substrate depth and decorations for the real water volume
• Results in litres, US gallons and UK gallons
• Save your tanks and open them again with one tap

WATER CHANGE PLANNER
• See how many litres or gallons a 10–50% water change is
• Find how many water changes it takes to bring a value such as nitrate from the current level down to your target
• Or the single water change percentage that reaches the target, with the step-by-step values after each change
• Takes your tap water value into account

DOSE BY LABEL
• Enter the product label (for example 5 mL per 40 L) and get the amount for your tank
• A simple proportion of the label; always follow the product instructions

UNIT CONVERTER
• cm ⇄ inches, litres ⇄ US/UK gallons, °C ⇄ °F, dKH/dGH ⇄ ppm

YOUR DATA STAYS ON YOUR PHONE
• No account, no sign-up, works offline
• Back up and restore your saved tanks with a file

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