Okay, so there are a number of these threads here and on other forums, but none seem to have a definitive answer, so here goes.. (This happened a few weeks ago; just getting around to asking about it..)

I have some AOG's that have never been touched (to this day), but every other type of Zoa I've had was wiped off the face of my marine microcosm over the course of a few nights.. Everything was fine (for months) and I had a few different colonies going, then - not corresponding with a new fish or other addition to the tank - each night a cluster would disappear.. And I mean up to 10 heads in a night (!). And the rock underneath them looked like it had been ground with a scouring pad..

Now, I'm aware that fish go rogue, that there are pest nudibranchs, giant amphipods, and nasty little snails that will attack zoas, but are they really able to mow down such large swaths of biomass in one night? I thought my urchins were eating them and even banished a tuxedo to the sump for a while. It didn't help..

All the threads out there talk about dipping the zoa rocks in FW, and a number of different products to kill the nasties, but I've got a ton of rock. Not one of these threads has a post where the originator follows up saying, I figured it out; it was a ____!

And I dunno what's up with my AOG's, they must taste like sh*t. lol..

Anybody heard of non-anecdotal, definitive Root Cause on any of these mystery midnight zoa munching cases? Sorry for the book..