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Reef calculator · reviewed 2026-05-01
Reef tank flow calculator
Soft and LPS reefs often start around 10-20x turnover, mixed reefs around 20-40x, and SPS systems around 40-60x.
target display flow = display gallons x reef-goal turnover
Display flow
2,250 GPH
The 20-40x band gives 1,500-3,000 GPH before aquascape and pump placement.
What this catches
The first-order mismatch: too little capacity, unsafe wattage, weak turnover, missing coverage, or a budget that ignores supplies.
What it cannot catch alone
A single calculator cannot verify every product, livestock choice, chamber fit, vendor listing, or future stocking plan.
Why open the planner
The planner combines this result with equipment categories, budget tier, bioload, and compatibility rules.
Embed this calculator
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