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Freshwater Aquarium

Discus Tank

A dedicated tank for discus (Symphysodon spp.) - the "king of aquarium fish" - demanding warm, soft, acidic Amazonian water.

Difficulty: Advanced Tank Size: 55g+ Recommended: 90g Budget: $600-$4,000 Setup Time: 60 days

📖 Overview

Discus are among the most demanding freshwater fish in the hobby. They require warmer temperatures (82-86 F), softer water (GH < 4), and lower pH (6.0-6.8) than most tropical fish. They are shoaling species - keep 6 minimum. Adult discus reach dinner-plate size and are stunning - striped, spotted, or solid in a range of colors from cobalt blue to fire red.

💧 Essential Parameters

Temperature: 82-86 F. pH: 6.0-6.8. GH: 1-4 dGH. KH: 1-3 dKH. TDS: 100-200. Nitrate: under 10 ppm. Requires very high water quality.

⚙️ Key Equipment

Large canister filter (2-3x turnover). Heater sized for 82-86 F (5W/gal in cold climate). Full-spectrum LED (subdued if wild-strain). RO or RO/DI water. Ceramic diffuser for oxygen at high temp.

🐟 Stocking Recommendations

Discus (6+ for shoaling comfort). Compatible tankmates: cardinal tetras, rummy-nose tetras, sterbai corys (warm-tolerant), Amano shrimp, small plecos.