Emerald Crab eating zoa??

[k3nnyp]

I have two zoa colonies, one ony 10+ polyps while the second has a few dozen. They looked great since I got them a few months ago and started doing better when I increased my specific gravity and started making my own water (Salinity Salt).

Almost overnight my two colonies closed up and shrunk dramatically. Both colonies are starting to come back but the large colony is coming back very slowly at best. I noticed at least two polyps that are completely missing. I have not identified any reason for the change, although I have recently been struggling a little bit with algae. Water parameters appear to be fine.

Last night I saw one of my emerald crabs pick at my zoas, although did not appear to be eating the zoa just picking at the rock between polyps. Today I stumbled across a post that claimed detailed at least a couple incidents of emerald crabs eating zoa's.

I have had the emeralds for probably a month before any sign of deterioration of the zoa colonies.

Anyone else have such an experience? I'm going to try to catch some tonight ( I have 5 hidden in the rock ) and banish them to my sump.

 

[qasimja]

ive read before that they could possibly eat zoas on another couple forums

 

[cbj25]

I'm currentlytrying to catch one, I had two full zoa frag discs disappear from the disc but what had grown on my rock is still healthy, I think he just scraped them off the disc... He also got to a colony (100+ polyps) of some nice orange zoas. All perams check out and he is the only thing I could think of. After seeing him picking at a colony I moved all of my nice zoas into another tank for safe keeping. I wish they only ate teal palys!

 

[acroholic]

Emeralds can also eat small fish when they get large enough. Most crabs are opportunistic, so anything they can get/catch and eat they will.

 

[k3nnyp]

Thanks for the info, not to figure out the best way to catch them.

 

[cbj25]

Come from behind them and pin with your thumb then flip them up and catch with net. Good luck!