Gardening & Pets
Aquarium Stocking Calculator
Check if your fish tank is under- or overstocked using adult fish sizes, plants and filtration.
Enter your details
gal
in
Your result
Stocking level
62.07%
62% stocked (18" of fish in ~29" capacity). Comfortably stocked — room to add.
Assessment
Comfortably stocked — room to add
Adjusted capacity
29 inches
Room remaining
11 inches
About this calculator
Applies the classic one-inch-of-adult-fish-per-gallon guideline, with credit for live plants and oversized filtration (which boost bio-capacity). Use adult sizes, not store sizes — that 1-inch common pleco becomes 18 inches.
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