Jason,
I agree with Wendy. Pods of all varieties and sizes will get rid of anything if it doesn't do well. Perhaps something fell on those zoos or they got stung by something and it did them in. Down current from a rock anemone that takes a wild poop in the middle of the night will destroy a colony of zoos that are not established. Sounds like something got to that rock in your tank and then the pods cleaned it up. I did have an established colony of palythoa go like that once for no apparent reason. They got sick and slimed up, then died. I figure anything I get is some kind of risk, especially in the beginning.
