7 calculators
Curved Aquarium Volume Calculators
Curved tanks have at least one panel that is not flat. Cylinders and bowls are fully round, while bow fronts, bullnose and round end tanks combine straight sections with arcs. Each needs a formula that includes π somewhere, and each has a measurement that is easy to take in the wrong place.
How curved tanks are measured
Radius is always half the inside diameter. On bow fronts, separate the flat depth from the extra bow depth. On bullnose and stadium tanks, measure overall length tip to tip. For bowls, find the widest inside diameter rather than the opening.
Formula differences
Round shapes use π × r² for the floor area, halved or quartered for partial cylinders. Bow fronts add a half-ellipse, π × (L/2) × B ÷ 2, to a box. Bowls use the sphere formula π × d³ ÷ 6 with spherical-segment adjustments for partial fills.
Common mistakes
- Entering the diameter where the radius is required, which quadruples the result.
- Treating a bow front as a rectangle using the centre depth.
- Measuring a bowl across its opening instead of at its widest point.