[NYreefNoob]

8.15 isnt low on ph, mine flux's 8.-8.2 and just because you mainly have lps doesnt mean to keep your cal under 400 450 is really ideal, frogspawn and such still need cal to grow as well as do most lps , as for the zoa's re they a newer addition ? did you dip them before putting into tank ? check it for nudi's also, also could be a parasite, ive also found that usually twice a year i have some zoa's just start to melt, never figured it out, i have around 30 different morph's also watch the blenny, i use to have a starrey eyed that use to eat them, what test kit are you using ? phos is never zero, btw other then alot of zoa's my tank is mainly sps