Estimate the volume of a bow front fish tank in litres and gallons.
Open live calculator →A 90 cm bow front with 40 cm side depth, a 10 cm bow and 50 cm water height holds about 215 litres.
Bow modelled as a half ellipse—compare with the manufacturer's stated capacity.
Bow front aquariums add a curved section to a rectangular body. This calculator models the bow as half an ellipse to estimate total capacity from four simple measurements.
The live tool updates immediately and shows the result in the units commonly used by aquarium keepers around the world.
Measure bow depth at the centre of the curve.
Use internal dimensions where possible.
Compare with the manufacturer's stated capacity.
The calculator models the bow as half an ellipse added to the rectangular body, which lands within a few percent for typical commercial bow fronts. The manufacturer's stated capacity, where available, remains the reference.
Measure the tank's total front-to-back depth at the centre of the curve, then subtract the depth at the sides. The difference—how far the glass bows outward—is the bow depth the calculator needs.
Slightly, for the same footprint: the curved front typically adds 5–15% over the equivalent rectangle, which is exactly what the elliptical term in the formula estimates.