The one and only time I tried this coral the same thing happened to me.Looks like red dragons and me aren't meant to be.
Woke up this morning to a bleached white piece. Was growing really well with deep red color and purple tips so not sure what happened.
Params are stable ans everything else in the tank is growing fine.
Only change i made recently is swapping out gilter bag and introducing new chaeto from a clean system.
My alk and pH did drop a bit but nothing too extreme...mostly acceptable ranges. Alk 9.5 from 9.8, pH from 8.2 to 7.8 - 8.0.
Literally RTN over last 24 hours.
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