Disease prevention beats treatment - here's the protocol that works. 1. Quarantine every new fish 30 days minimum. Use a separate 20-gallon tank with mature sponge filter. Treat prophylactically: SW = 14 days copper + 2x prazi at days 1+14. FW = prazi + general cure 7 days. Observation only after that. 2. Maintain stable water parameters. Test ammonia + nitrite + nitrate weekly. Reef = also alk/Ca/Mg/PO4. Match temperature within 2°F across water changes. Sudden parameter swings stress fish + invite disease. 3. Varied high-quality diet. 2-3 different foods rotating: high-quality pellet (NLS, Hikari, Fluval Bug Bites), frozen mysis or bloodworms 2-3x weekly, occasional live brine. Add garlic supplement (Selcon, Vita-Chem) for marine. Strong nutrition = strong immunity. 4. Avoid overstocking. Use AqAdvisor or our stocking calculator. Overcrowded fish stress + immunocompromise. 5. Minimize stress. No aggressive tankmates (research compatibility). No bright lights all day - need dim/dark periods. Use soft nets or barehand transfer. Avoid bumping the tank or sudden movements. Match destination water before transferring. 6. Disinfect everything between tanks. Nets, gravel vacuums, buckets - dedicated per tank or 10% bleach soak + rinse 3x. Cross-contamination spreads disease. 7. UV sterilizer. 9-13W UV catches free-swimming parasites + bacteria. Optional but reduces ich/velvet outbreaks dramatically.
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