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Each tool explains its assumptions and shows a worked example. Inputs stay temporarily in this tab; unit choices are remembered in this browser.
- Aquarium water volume calculatorEstimate actual water in a rectangular aquarium from internal dimensions, water height and solid displacement, in liters and US gallons.
- Salinity and specific gravity converterConvert 0–42 ppt salinity and specific gravity using the aquarium’s shared UNESCO EOS-80 calculation at a 25/25°C reference.
- Aquarium water change volume calculatorConvert your chosen aquarium water-change percentage into liters or US gallons, using actual system water volume.
- Nitrate reduction and water change plannerEstimate one or repeated equal water changes for a nitrate target, including replacement-water nitrate and actual aquarium volume.
- Brackish water mixing calculatorPlan a batch from two measured salinities, or calculate the replacement-water salinity needed for a chosen tank change.
- Aquarium substrate quantity calculatorEstimate substrate-bed liters, dry mass and whole bags from aquarium footprint, front and back depths, and your product’s bulk density.
- Aquarium electricity cost calculatorEstimate light, pump and heater energy cost using watts, daily hours, an adjustable heater duty cycle and your electricity tariff.
- Total aquarium weight calculatorEstimate aquarium load from actual water volume and density, tank, substrate, rock, equipment, cabinet and other component masses.
- Aquarium product dose scaling calculatorScale standard Seachem Prime or Flourish metric label amounts, or a conditioner/fertilizer label ratio you enter, with an explicit water-volume basis.
Free calculations, optional app records
Calculate and read the complete result here without an account. TankForge Free can help you create a tank and start a water-test log. Supported in-app saved calculator recipes, plans and history require Pro. Browser results are not transferred into the app.