THE QUIET TOOLS
Small calculations.
Better decisions.
12 free, no-account tools to take the guesswork out of tank sizing, water chemistry, feeding, stocking, heating, and maintenance. No subscription, no black box.
Tank Volume Calculator
Calculate your aquarium's actual water capacity from dimensions — litres, US gallons, and Imperial gallons, plus weekly water change guidance.
Open tool →Water Change Calculator
Find out exactly how much water to replace. Enter your tank volume and change percentage to get a precise replacement amount.
Open tool →Feeding Calculator
Get a simple feeding recommendation based on fish type, size, and count. Built for beginners who want a clear routine.
Open tool →Stocking Calculator
Estimate how many fish your tank can safely hold. A rough reference tool — not an absolute rule — with responsible ranges.
Open tool →Heater Wattage Calculator
Determine the right heater power for your tank based on volume and the temperature gap between room and target.
Open tool →Temperature Converter
Convert between Celsius and Fahrenheit instantly. A small but handy reference for aquarium temperature management.
Open tool →CO2 Calculator
Estimate dissolved CO2 from your pH and KH readings, with a live danger readout so you can keep planted tanks safe.
Open tool →Ammonia Toxicity Calculator
Work out how much of your total ammonia is the toxic free form, based on pH and temperature — the number that actually matters.
Open tool →Water Hardness Converter
Convert between dGH, ppm, mmol/L and French degrees so any care guide or test kit makes sense at a glance.
Open tool →Aquarium Weight Calculator
Estimate the true filled weight of your tank — water, substrate, glass, and decor — before you trust a shelf or stand.
Open tool →Dosing Calculator
Calculate the exact mL of fertiliser or medication to add from your tank volume and dose rate, in litres or US gallons.
Open tool →Filter Flow Calculator
Find the right pump turnover for your tank and stocking level, with a head-loss allowance and US gph conversion.
Open tool →Built with
measurable care.
Each tool is designed to answer one question clearly, without noise or upsell. Free to use, no account needed.
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