55 gallon tank: dimensions & setup math
48 × 13 × 21 inches (L × W × H). Rounded planning dimensions; measure your tank.
55 nominal gal · about 606.03 lb with water, estimated glass and 2-inch gravel.
Estimated working water uses 85% of nominal: 46.75 US gal. The volume tool instead applies 85% to geometric volume. Neither is a measured fill.
Eight answers for this tank
- Tank volume
56.73 US gallons · 214.74 litres
- Gravel & substrate
72.22 lb gravel for a 2-inch bed
- Heater wattage
165–275 W planning range
- Filter flow
220–330 GPH for a community
- Stocking guide
624 in² surface · 48-inch swimming length
- Water changes
11.69 US gal for a 25% water change
- Dechlorinator dose
5.5 mL Prime for 55 US gal of new water
- Filled weight
About 606.03 lb filled (without stand)
Plan around this footprint
This 55 gallon plan uses 48 × 13 × 21 inches and 624 in² of floor. Compared with the 50 gallon (648 in²), its footprint is 3.7% smaller. Medium setup: place equipment so water circulates along the full length, including behind hardscape.
Dimensions and limits
Aqueon size chart. Listed dimensions are representative, not exact catalog measurements. Names identify marketed sizes; geometry explains why the calculated gallons can differ. Weight excludes the stand, rocks and equipment.