Reef calculator · reviewed 2026-05-01

Reef build checker before you buy

The safest pre-buy check is cross-category: tank, reef goal, bioload, light, flow, heat, filtration, water, and livestock all have to agree before the cart becomes the build.

build passes when every required category clears its rule threshold
Skimmer target
150 gal rating

Light, medium, and heavy targets are 113, 150, and 188 gallons of skimmer rating.

Heater safety band
190-375 W

Use two heaters around 95 W each, preferably controller-backed.

Display flow
2,250 GPH

The 20-40x band gives 1,500-3,000 GPH before aquascape and pump placement.

Return pump rating
750-1,500 GPH

That aims to deliver 375-750 GPH after about 50% plumbing loss.

Light coverage
864 sq in

For this goal, use the 150-250 PAR band and cover the full 864 sq in footprint.

Startup budget
$3,500-$5,575

Monthly consumables often land around $60-$120 before livestock surprises or upgrades.

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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