Tank capacity
— L · — US gal
Stocking: — · Filter turnover: —
| Species | Qty | Adult size | Bioload |
|---|
How the math works
Volume = L × W × H (in cm) / 1000 = litres. We subtract 10% for substrate, rocks and equipment displacement. The outdated "1 inch per gallon" rule ignores body shape — a 30 cm goldfish produces 50× the waste of a 5 cm tetra.
Bioload sums species-specific waste ratings (low / medium / high / very high). Filter turnover should be at least 4× tank volume per hour for community tanks, 6–10× for heavily stocked or messy fish like goldfish and cichlids.