Help! Something is eating my Zoanthids!

[Drimo]

I have had a problem with something eating my zoos. I would say they have declined over 60%. Here is a picture of the colony from 3/3/2008:

And here is a picture of the same colony on 7/20/2008:

I thought it was my two Emerald crabs, but I removed them and the decline continued. I also had two aiptasia spring up so that is why there is a white spot. Sadly, some of the zoos around the aiptasia also died. I don't think that had an overall effect on the colony because the decline started well before I removed the aiptasia. I also set up a webcam during the day to see if any fish were picking at them but none of the fish touched the zoos.

But at night, I did find tons of amphipods on the zoos. I read some at WetWebMedia that amphipods can eat zoos if they are in high population. Here is a picture of the colony crawling with amphipods from two days ago:

I don't have anything to control my pod population, so now I plan to get a six-line wrasse, but in the meantime I did a freshwater dip of the rock (upon advice read at WetWebMedia) and a lot of amphipods fell off, but very few of the zoos have opened back up and the mushrooms look like they have melted.

It makes me sad because I have done something wrong and I don't know what it is yet. Any advice?

[CarmieJo]

I would suspect zoa eating nudis, soiders or sundial snails, before amphipods. Here is a guide Zoanthid Predators, Irritaters, & Diseases that is helpful.

[Drimo]

I initially thought nudis as well but didn't find any. Is there some way I can tell other than just closely inspecting the area?

[lReef lKeeper]

not that i am aware of, but there should be something in the link that Carmie sent, that tells you how to find them. ZoaID is a great site.

[CarmieJo]

You just have to look for them. They are really really small.