Best 55-gallon aquariums for large community freshwater or smaller cichlid. Top picks across budget tiers, what livestock fits, what to avoid, dimensions, weight, and FAQ. Updated May 2026.
Most-sold 55g. Width is a tradeoff vs 75g but cheaper + lighter.
Includes LED + canister filter + heater starter kit.
Frequent sale at Petco $1-per-gallon promotion ($55).
Suitable:
Avoid:
Beyond the tank itself, you'll need:
Use the stocking calculator to verify your livestock plan, the weight calculator to confirm your floor can handle it, and the electricity calculator for ongoing operating cost.
Standard 55-gallon aquarium dimensions: 48"×13"×21". Filled weight ~550 lbs.
~550 lbs filled (tank + water + sand + rock). Standard residential floors support ~40 lb/sq ft live load - tanks of 55g+ should be placed over a load-bearing wall or perpendicular to floor joists.
Yes - small marine setups (FOWLR or nano reef) work in 20g+. The reef setup options for this size are documented on the 20g FOWLR setup guide.
Total 55-gallon build cost varies by tier: budget $330-660, mid $660-1375, premium $1375-2750+. Use the reef build calculator for detailed breakdown.
Browse the full aquarium-by-size buying guide for 11 other tank sizes. Or jump to the step-by-step setup guides, the stocking blueprints, or the calculator collection.