TankMathLess guesswork. Better tank plans.

Filled aquarium weight calculator

This intentionally adds nominal water capacity plus gravel without subtracting displacement. It is a planning allowance, not a certified structural load. Assumed glass thickness is 3/16 inch up to 20 gal, 1/4 up to 55, and 3/8 above; real panes and bracing differ. Never use these estimates to design or build a tank. Roughly 10 lb/gal is only a shortcut; rocks, equipment, lids and the stand add weight. Use a suitable aquarium stand and get qualified floor advice if needed.

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Use your measurements and current product instructions. These are freshwater planning estimates.

Worked example: 20 gallon long

Water: 20 nominal gal × 8.34 = 166.8 lb. Five glass panes: (30 × 12 + 2 × 30 × 12 + 2 × 12 × 12) × 0.19 in × 0.0943 lb/in³ = 24.19 lb. Add 41.67 lb for 2-inch gravel = 232.65 lb.

ComponentEstimated lb
Nominal freshwater fill166.8
Glass panes24.19
2-inch gravel bed41.67
Total, excluding stand / equipment232.65

Water density reference; water is approximated at 8.34 lb/gal. Glass density is an assumed 0.0943 lb/in³; manufacturer empty weight is preferable.

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