Why won't my zoas open?!?

[Kicknballs]

I have a small group (about 10) that have been in my 20L for a few months, and a larger group of about 80 that i bought last weekend. The smaller group will only open up about half way, maybe once a week. I have tried moving then to different spots (more/less light/flow), but no help. Only a few of the larger colony will open fully, and about half haven't opened at all. The tank's parameters are good. Lighting is a 39x4 T5 Fish Need It with ATI bulbs that are about 3 months old. Tank has been running since February.

Any and all help/advice very appreciated!

[cbianco]

Here's a short list of things that could be causing them not to open.

-Flow
-Lighting
-Other corals
-Predator
-Tank parameters

Just some ideas.

Christopher :)

[clone]

look for some zoo eating nudies. If you do find some tweez them off the zoas. Then go back and look for the nudies eggs.

[jpond83]

put them in a high flow area

[firecoral3msd]

My zoas seem to open and react well with doses of Marine C. You could try that. You can get Kent Marine C from your LFS. If not from there, you can get it online. Kent Marine Zoe can help open up zoas too. I think because it has vitamin C in it.

[Kicknballs]

I haven't seen any critters on them. I'll move them to a more high flow area and try then Marine C. Thanks everyone... I'll let you know how they respond.

[stoneroller]

Did you dip them before you placed them in the tank? You may have brought in some zoa pests with the colony. There are many "critters" that come in on zoa colonies: snails, spiders, nudis, etc. I suggest two things: one, take both out and give them a good dip (RO water with lugol's or coral dip) and shake the heck out of them; inspect every polyp closely for nudi eggs (white, spiral-shaped strings of little eggs). Two, blast them with a turkey baster or powerhead, keep the colonies clean of detritus.

Ok, three things... post some pics!

[stoneroller]

PS. Keep a reef-safe wrasse to protect your zoa-investments.

[saabtech]

my tank got cold once and the zoo/s didnt open for almost a week????