Tools/Stocking Calculator

Reef Tank Stocking Calculator by Tank Size

A rough bioload read by fish size tier, not a compatibility check. Run any specific pairing through the Compatibility Checker separately.

Your Tank & Fish

Estimated bioload

Moderate

room for one or two more small-to-medium fish with good filtration

Estimated gallons "used"

52 gal

Tank volume

75 gal

This is hobbyist convention, not a hard rule. No peer-reviewed source sets marine stocking density. This estimate uses a widely-repeated adjustment to the freshwater "1 inch per gallon" rule (small fish ~1in/gal, medium ~1in/2.5gal, large ~1in/5gal) with average adult sizes assumed per tier. Reef bioload actually depends more on filtration capacity, feeding habits, and coral/invertebrate load than fish length alone. When in doubt, understock, not overstock.

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