Aquarium Stocking Calculator

Calculate the optimal number of fish for your tank size. Our calculator uses the classic “1 inch per gallon” rule with adjustments for filtration and fish temperament.

Tank & Fish Details

Tank Size (Gallons)

Filtration Level

Fish in Your Tank

Tank Status

How This Calculator Works

• Base Rule: 1 inch of fish per gallon of water

• Filtration: Better filtration allows higher stocking

• Temperament: Aggressive fish need more space

• Adult Size: Based on full-grown fish, not current size