Aquarium Volume by Brand

Aqueon

Standard glass rectangles. Dimensions are published exterior sizes.

Model	Exterior L × W × H (in)	Label	Calculated	Litres	Difference
2.5 Mini	12.19 × 6.13 × 8.13	2.5 gal	2.63 gal	10.0	+5%
5.5	16.19 × 8.38 × 10.5	5.5 gal	6.17 gal	23.3	+12%
10 Leader	20.25 × 10.5 × 12.56	10 gal	11.56 gal	43.8	+16%
15	24.25 × 12.5 × 12.75	15 gal	16.73 gal	63.3	+12%
20 High	24.25 × 12.5 × 16.75	20 gal	21.98 gal	83.2	+10%
20 Long	30.25 × 12.5 × 12.75	20 gal	20.87 gal	79.0	+4%
29	30.25 × 12.5 × 18.75	29 gal	30.69 gal	116.2	+6%
30 Breeder	36.19 × 18.25 × 12.94	30 gal	37.00 gal	140.1	+23%
40 Breeder	36.19 × 18.25 × 16.94	40 gal	48.43 gal	183.3	+21%
55	48.25 × 12.75 × 21	55 gal	55.93 gal	211.7	+2%
75	48.5 × 18.5 × 21.13	75 gal	82.07 gal	310.7	+9%
90	48.5 × 18.5 × 25.38	90 gal	98.58 gal	373.2	+10%
125	72.5 × 18.5 × 23.38	125 gal	135.75 gal	513.9	+9%
150	72.5 × 18.5 × 29.5	150 gal	171.29 gal	648.4	+14%

Fluval

Flex models have a bow front; the rectangular figure here overstates them. Spec models include a rear filter chamber.

Model	Exterior L × W × H (in)	Label	Calculated	Litres	Difference
Flex 9	14 × 13 × 13	9 gal	10.24 gal	38.8	+14%
Flex 15	16 × 15 × 15	15 gal	15.58 gal	59.0	+4%
Spec III	10 × 8 × 11.5	2.6 gal	3.98 gal	15.1	+53%
Spec V	17.2 × 11.2 × 9.8	5 gal	8.17 gal	30.9	+63%
Spec 16	21.5 × 11.5 × 17	16 gal	18.20 gal	68.9	+14%

Marineland

Standard framed glass sizes.

Model	Exterior L × W × H (in)	Label	Calculated	Litres	Difference
2.5	12 × 6 × 8	2.5 gal	2.49 gal	9.4	0%
5	16 × 8 × 10	5 gal	5.54 gal	21.0	+11%
10	20 × 10 × 12	10 gal	10.39 gal	39.3	+4%
20 High	24 × 12 × 16	20 gal	19.95 gal	75.5	0%
20 Long	30 × 12 × 12	20 gal	18.70 gal	70.8	-6%
29	30 × 12 × 18	29 gal	28.05 gal	106.2	-3%
55	48 × 13 × 20	55 gal	54.03 gal	204.5	-2%
75	48 × 18 × 21	75 gal	78.55 gal	297.3	+5%
110	48 × 18 × 30	110 gal	112.21 gal	424.8	+2%

Coralife

BioCube all-in-ones have a rear filtration chamber that removes roughly a fifth to a third of the exterior volume.

Model	Exterior L × W × H (in)	Label	Calculated	Litres	Difference
BioCube 16	15 × 16.75 × 17.5	16 gal	19.03 gal	72.1	+19%
BioCube 32	20.25 × 21.875 × 21.5	32 gal	41.23 gal	156.1	+29%

Why calculated volume differs from the label

Calculated figures use exterior dimensions and therefore overstate the interior. Manufacturers round the label to a familiar size and sometimes quote the interior or a fill-line volume. All-in-one tanks with rear filter chambers, such as the BioCube range, lose a further fifth to a third of their exterior volume to the chamber. For equipment sizing and dosing, measure inside the glass and use the matching shape calculator rather than either number here.

Frequently asked questions

Because the dimensions are exterior and include the glass. Interior volume is typically 5 to 12 percent lower, which lands close to the label.

No, the Flex has a curved front, so a rectangular calculation overstates it. Use the bow front calculator with your own measurements.

Send the model and published dimensions through the contact page and we will consider it for the table.