This all started with my speckled krak it went from open and happy to shriveled on the brink of death in about 2 days time. All my other zoas are quickly following and idk what to do, I’ve already dipped them in coral rx and did a massive water change and it keeps spreading. The odd thing is none of the zoas on my rock seems to be affected only the ones on my rack, that sit at the same hight as the zoas on my rock. I haven’t made any adjustments to light or temperature, none of my other corals seem to be exhibiting signs of death. Please help all information is helpful.