Reef calculator · reviewed 2026-05-01

Return pump GPH calculator

Most sumped reef systems want roughly 5-10x system turnover delivered after head loss.

rated pump GPH = target delivered GPH / head-loss factor
Return pump rating
950-1,900 GPH

That aims to deliver 475-950 GPH after about 50% plumbing loss.

How to use this result and review notes

Uses ReefCrafter rule math

This tool is a doorway into the build planner. Use it for the quick number, then check the surrounding equipment before buying.

Reviewed by Max Rodes on 2026-05-01 against the connected guide, equipment sizing methodology, and planner formula.

Calculators expose planning assumptions, not guarantees. See the editorial policy.

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

Free to use on your site, forum post, or club page. Paste this where you want the live calculator to appear.

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