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Tank Specifications
US gallons. Common sizes: 10, 20, 29, 40, 55, 75, 125
Affiliate Disclosure: This calculator is free to use. Some product links are affiliate links. Product links and pricing are for the US market. Equipment sizing calculations work for any region.
How This Calculator Works
- Filter: Sized at 4-10x tank volume turnover per hour depending on tank type. Reef tanks need higher flow. Canister filters recommended for 40+ gallons, HOB (hang-on-back) for smaller tanks.
- Heater: Sized at 3-5 watts per gallon depending on room temperature differential. Tanks over 60 gallons should use two heaters for redundancy and even heat distribution.
- Lighting: Low-light freshwater needs 15-25 lumens per gallon. Planted tanks need 35-50. Reef tanks need PAR-rated lights with specific spectrum requirements.
- Substrate: Calculated at 1-2 lbs per gallon for standard depth (1.5-2" freshwater, 3-4" planted, 1-2" sand bed for saltwater).
- Stocking: Based on modified "inch per gallon" rule adjusted for tank shape, filtration capacity, and species bioload. Conservative estimates for healthy, sustainable tanks.