Zoanthids closed

So I caught my large hermit crab crawling all over my zoanthid colony today. Is it normal for them to be closed or half opened for a couple of days? Also is it too much to add a bangaii cardinal and frogspawn at the same time? Thanks

 

How big is your tank?

My Zoas will close for about a day if anything seriously upsets them, they are pretty hardy.

 

my hermit always walk over my zoa, they usually open back up within a couple mins after the hermit left, guess they are used to it.

 

How long have you had the zoas. If their new it could be a lighting or flow issue. As far as adding more it depends on when you last added fish to your system. You can add as many corals in at a time as you want the only thing corals do is use up calcium and alkalinity, but when you add fish you should wait 2 weeks to a month in between adding fish to give your bacteria some time to catch up to the bio-load. Hope this helps ya a little bit.

 

Keep an eye out for Zoanthid eating nudibranch's. I bought some zoa frags and after a couple of days in my system they closed up and wouldn't open. I thought they were just unhappy with their location, so I moved them around the tank to different locations, nothing helped, finally I found one of these little guys crawling around. I spent weeks trying to manually remove all these little pests but once I made some progress the Zoa's did open back up. I hope that this isn't your problem but just wanted to give you a heads up about it.