Goldfish Per Gallon Calculator

Calculate how many goldfish can safely live in your aquarium tank. Get stocking recommendations based on tank size and goldfish type.

Enter Tank Details Get Stocking Results

Tank Information

Different types have different space requirements

Stocking Results

Enter tank volume and click "Calculate Stocking" to see results

Goldfish Per Gallon Calculator

Goldfish may look small in pet stores, but they grow fast and need plenty of space. A Goldfish Per Gallon Calculator helps you determine how many goldfish your tank can safely support, based on tank size and fish type.

This tool removes the need for manual counting and reduces the risk of miscalculations.

On average, goldfish need about 10-20 gallons per fish depending on the variety. Fancy goldfish generally require less space than common varieties.

Calculation Formulas

Goldfish Stocking Guidelines

Volume Conversion

Gallons = Liters ÷ 3.785

Convert liters to US gallons for calculation

Fancy Goldfish

Fish Count = Gallons ÷ 10

Each fancy goldfish needs 10 gallons of space

Common/Comet Goldfish

1 Fish + (Gallons - 20) ÷ 10

20 gallons for first fish, +10 gallons for each additional

These formulas follow commonly accepted aquarium guidelines for healthy goldfish care.

Tank Stocking Examples

Recommended Stocking Levels

Tank Size Goldfish Type Recommended Fish Status
10 gallons Fancy 1 Safe
20 gallons Fancy 2 Safe
20 gallons Common 1 Safe
30 gallons Common 2 Safe
40 gallons Fancy 4 Safe
15 gallons Common 0 Too Small

These examples show safe stocking levels. Always err on the side of fewer fish for better water quality.

Final Thoughts

Goldfish thrive when given enough space. A Goldfish Per Gallon Calculator makes tank planning easy and accurate. Enter your tank size, choose the goldfish type, and get instant results you can trust.