its the only thing that really makes sense to me, other than disease. take it for what its worth, but there havent been any pictures that jump out to say "oh ya, thats disease 100%". so far, its all just been speculation, and possible of course, but the only thing that i would imagine that would kill that fast, would be quite noticeable by anyone here via picture, or by the owner themself. that doesnt seem to be the case, but i still dont rule it out.The thing is, any water issue I would guess would hurt the coral first right? But you may be on to something.
the water parameters, of course look fine, and i would suspect corals to be more delicate than most fish to react. but again, its such a new tank that it doesnt surprise me if the anemone isnt happy anyway, so its a toss in the air as to whats causing that. on the other hand, most of the other corals can live pretty easily, without showing signs of problems, minus the couple LPS in there. the LPS dont seem to be having problems, but they are also not really extending a ton, other than that torch.
at this point, im at a loss. there is just too much at such an early stage to give me any thoughts other than just guessing and throwing darts at the wall to see which one sticks