Starlight Tools directory
Aquarium Calculators
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This category covers aquarium planning and routine maintenance calculations: tank dimensions, working water volume, substrate quantities, water changes and running costs. It is intended to help fishkeepers organize measurements and understand the assumptions behind an estimate.
Measure the water you actually keep
Distinguish a tank’s stated capacity from its working water volume. Internal dimensions, fill height, substrate and decorations all affect that volume. Record whether a measurement uses litres, US gallons or imperial gallons before combining it with another value. For maintenance calculations, keep the amount replaced separate from the total capacity.
Planned tools will cover tank volume, substrate quantities, water changes and equipment costs. Browse our existing science tools for related measurement and calculation topics. Tank volume alone does not establish suitable stocking or animal-care conditions.