Tools/Powerhead Flow Rate Calculator

Powerhead Flow Rate Calculator

Get total system flow for your coral demand, then see how much your powerheads need to add once your return pump's flow is accounted for.

Your Tank

From the Return Pump Calculator, if you've already run it

Total system flow range

2,000-3,000 GPH

Return pump already provides

450 GPH

Powerheads need to add

1,550-2,550 GPH

split across 2-4 units for even coverage, not one oversized unit

Why this is a range, not a formula: these turnover multipliers are widely-practiced hobbyist convention from large-sample forum discussion, not a manufacturer or research-body standard. Actual needs depend on tank shape, coral placement, and powerhead overlap. A tall narrow tank and a wide shallow tank at the same gallons rarely feel the same at the same GPH.

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