Estimate an aquarium’s actual water capacity from internal rectangular dimensions, then account for substrate, rock, wood, and the unfilled space below the rim. The calculator reports liters, US gallons, and water weight. It is useful for treatment arithmetic and water-change planning when the manufacturer’s nominal tank size differs from the volume of water actually present.
The main result is estimated usable water volume after displacement. Use internal measurements and actual filled depth, not exterior dimensions, for the closest estimate.
Irregular tanks need a shape-specific volume method. Décor displacement is an estimate; measuring the actual refill volume after a full setup provides a stronger basis for sensitive dosing.
An aquarium measuring 90 × 40 × 45 cm internally has 162 gross liters. After 12% displacement, usable capacity is 142.56 L, or 37.66 US gallons, with about 142.56 kg of water.
No. Use it to check arithmetic and planning assumptions, then follow the applicable veterinarian, product label, welfare standard, or qualified care guidance.
A zero is accepted only where it represents no cost, no feed, no water change, or another valid absence. Values used as divisors or required physical dimensions must be greater than zero.
Actual results depend on conditions not fully represented by a compact model, including animal needs, measured consumption, losses, operating practices, and local prices.
Keep the unrounded value for planning. For medication or treatment measurements, use only the rounding and measuring method approved on the label or by the responsible professional.
Update them whenever weight, occupancy, tank volume, husbandry routine, prices, equipment use, or the underlying care plan changes.
| Input type | How to choose it |
|---|---|
| Physical measurement | Use an observed or measured value in the displayed unit. |
| Rate or percentage | Use the applicable care plan, product label, or operating record. |
| Planning period | Keep the period consistent with the formula and result. |