A corner bow front aquarium has two flat side panels meeting at a right angle in a corner and an outward-curved front glass connecting them. Its volume is the area of the right triangle in the corner plus the segment added by the curved front, multiplied by the height.
The two side panels are assumed to be equal. The side length is the distance from the corner to the end of a side panel; the bow depth is how far the front glass bulges out beyond the diagonal line that joins the two ends.
How is the volume of a corner bow front aquarium calculated?
Gross volume (litres) = (side² ÷ 2 + bow segment area) × height ÷ 1000. The bow segment is a circular segment whose chord is side × √2 (the diagonal) and whose height is the bow depth.
How to take the measurements
- Measure the side length from the corner to the end of one side panel on the outside, and confirm the other side is the same.
- Imagine (or stretch a string along) the diagonal line joining the two ends of the side panels.
- Measure the bow depth from that diagonal line to the farthest point of the front glass.
- Measure the height and glass thickness, then enter the advanced settings.
Worked example
For a corner bow front aquarium with side length 70 cm, bow depth 15 cm, height 60 cm, the gross volume is 207.5 litres. With 0.8 cm glass, no substrate and 2 cm of headroom, the net water volume is 187.1 litres.
Example sizes and their volumes
| Side length (cm) | Bow depth (cm) | Height (cm) | Gross (L) | Net water (L) | Net water (US gal) |
|---|---|---|---|---|---|
| 50 | 10 | 50 | 86.4 | 75.4 | 19.9 |
| 60 | 12 | 55 | 136.9 | 121.7 | 32.1 |
| 70 | 15 | 60 | 207.5 | 187.1 | 49.4 |
| 90 | 18 | 65 | 364.1 | 333.5 | 88.1 |
Net water volume assumes 0.8 cm glass, 0 cm substrate and 2 cm headroom; results are approximate.
Frequently asked questions
How do I choose between a quarter-cylinder and a corner bow front calculator?
Use the quarter-cylinder calculator if the front is exactly a quarter circle. If the curve is shallower or deeper and you know its depth, use the corner bow front calculator.
What bow depth should I enter?
Enter the perpendicular distance from the diagonal line joining the two side panel ends to the farthest point of the front glass.
Is the result correct if the side panels are unequal?
This calculator is for tanks with equal sides. For unequal sides, check the manufacturer's stated volume.