Pets

How Many Gallons Is Your Fish Tank?

Built by Kevin Glover · @gloverbuilds · Verified formula

Calculate aquarium volume in gallons and liters from tank dimensions. Rectangular, bowfront, and cylindrical tanks.

📅 Updated April 2026 ✅ Formula verified 📖 4 min read 🆓 Free · No sign-up

In this article

Why Exact Volume Matters
Weight Considerations

Fórmulas

Retangular: C × L × A (cm) ÷ 1.000 = litros. Aquário de 90×40×50 cm: 180 litros. O volume real é menor que o nominal porque substrato e decoração deslocam água. Um "200 litros" contém provavelmente 170-180 litros reais.

Escolhendo o Tamanho

Iniciantes: 80 litros mínimo. Intermediário: 200 litros. Avançado: 300+ litros. NUNCA comece com 20-30 litros — volumes pequenos são os mais difíceis de manter estáveis.

⚡ CalcWolf Insight

Subtract 10-15% from your calculated volume for the "real" water volume after substrate, rocks, wood, and equipment displace water. A 20-gallon tank with 2 inches of gravel and a few decorations holds about 17-18 gallons of actual water.

Frequently asked questions

Como calcular?▾

C × L × A em cm ÷ 1.000 = litros. Meça dimensões internas.

Qual tamanho para começar?▾

80 litros mínimo. Quanto maior, mais estável e mais fácil de manter.

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Kevin Glover · @gloverbuilds

Founder, CalcWolf · GLVTS · Blickr

All formulas sourced from primary references — IRS publications, peer-reviewed research, and official standards. Results are tested against independent reference calculators before publishing. Rates and brackets updated when official sources change. Editorial policy →