I started with some rocks from my previous system a (20 gallons) that had been running for about 5 months and added some extra rocks. For sand I used a brand new of the Fiji Pink live sand.I agree with the “take it slow” advice here but doubt 10% weekly water changes, or high phosphates, are main contributors to your torches and hammers dying,
You could have a bacterial issue going on especially if you are seeing recurring BJD on these corals. Did you start the tank with dry rock/sand by any chance?


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