Improving water quality is essential for successful discus fish care. Follow these practical steps to maintain stable, healthy water conditions: Regular water changes Replace 20–30% of aquarium water weekly. Larger tanks allow more frequent or larger changes. Use dechlorinated, temperature-matched water to avoid shock. discus fish (depositphotos.com) Efficient filtration Use a high-quality canister or hang-on-back filter rated for more than the tank volume. Combine mechanical (foam or floss), biological (ceramic rings, bio-media), and chemical (activated carbon or Purigen) filtration. Clean mechanical media regularly; avoid over-cleaning biological media to preserve beneficial bacteria. Monitor and control water parameters Maintain temperature 82–86°F (28–30°C), pH 6.0–7.0 (discus prefer slightly acidic), and soft water (dGH 1–8). Test ammonia, nitrite, nitrate, pH, and general hardness weekly. Immediate action is required if ammonia or nitrite are above 0 ppm. Manage nitrates and orga...