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Reef calculator · reviewed 2026-05-01
Reef lighting coverage calculator
A reef light has to cover the tank footprint and hit the PAR band for the coral goal.
fixture coverage >= length x width and PAR >= coral target
Light coverage
864 sq in
For this goal, use the 150-250 PAR band and cover the full 864 sq in footprint.
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.
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