Free Tool
Aquarium Tank Size Calculator
Calculate the right tank size for your fish. Get stocking recommendations and avoid overstocking.
Your Tank Size
gallons
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How to Calculate Aquarium Stocking
Proper stocking is essential for healthy fish. Overstocked tanks lead to poor water quality, stressed fish, and disease outbreaks. Use our calculator to ensure your fish have adequate space.
The One Inch Per Gallon Rule
A common guideline is one inch of fish per gallon of water. However, this is just a starting point. Factors like fish body type, activity level, and filtration capacity all affect stocking limits.
Understanding Stocking Levels
- Under 50%: Lightly stocked - Easy maintenance, room for more fish
- 50-80%: Moderately stocked - Good balance of fish and maintenance
- 80-100%: Heavily stocked - Requires excellent filtration and frequent maintenance
- Over 100%: Overstocked - Reduce fish population or upgrade tank