The 8 reef-tank mistakes that kill coral. Stable parameters, light, flow, and sourcing.
Daily alk swing >1 dKH/24h triggers RTN in SPS. Test 2x weekly during dosing dial-in; once/week thereafter. Never make corrections of more than 0.5 dKH per day.
SPS demands stable parameters + clean water + high flow. Master soft + LPS for 6-12 months first; build the discipline of weekly testing + dosing before adding SPS.
Every coral piece carries hitchhikers (AEFW, red bugs, nudibranchs, flatworms, vermetids). Dip in CoralRx/Bayer for 5+ minutes. Quarantine for 30 days. Costs $0.50; saves $500+ in coral collection wipeouts.
A reef tank under SPS lighting (250+ PAR) with budget LEDs = bleached + STN coral. Either match lighting to livestock requirements or stick to LPS/soft coral.
Tanks without an Apex/Hydros controller fail silently when heaters stick on or ATOs malfunction. Controllers + alerts pay back the first incident.
Hydrometers drift 1-3% within a year. Use a refractometer (calibrated monthly with 35 ppt solution). Salinity-shock from a drifted hydrometer kills corals + fish.
A new reef tank cannot support its full bio-load. Add fish + coral over 6-12 months, not 6 weeks. Watch parameters after each addition; let them stabilize before the next.
Tap water carries phosphate, copper, nitrate, and chloramines that fuel algae and kill coral. RODI is mandatory for any reef tank, period.
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