green zoos don't open up

[beach]

have 4 systems withe green zoos.my 90 disply has 4 48" vho excellent water para and the polyps are shriveled up never open.my yellow polyps are spreading like crazy.my 55 has 4-48" vho and the green zoos look great at the top of the rock only 4 " from the lite.in my prop tank(400w mh) the zoos look great for awhile then don't extend right and have very small buttons instead of the large ones in the other tanks.all are related and are propagated from the same colony.i realze probably to much lite in the prop tank but don't get in the vho tanks.any respons appreciated.thanks beach

[TS]

I would take a good look at the different flow patterns of the colonies in your tanks.

Another possibility would be available nutrients- refugium in one, not the others? skimmers?

Try to isolate the differentiating factor, obviously it's not lighting...so what is it?

Travis

[blueoceandiver]

I had the same problem i had to post to find out what was wrong.Turns out i had zoo nudibranch,the little buggers were killing the zoos they went skinny and lost mass.They are very hard to see but once u do you can spot them with no problem.a fresh water dip also helped.

[MUCHO REEF]

Zos will periodically close up for a week or two to clean themselves sometimes. This process allows them remove "surface mucus and tissue layers are sloughed off, ridding the colonies of surface algae, sediments, and waste". My zos seem to close up one colony at a time for a week and they always come back around. I routinely use a power head to do a surface cleaning of all of my zos once per month.

If it's Nudis, a fresh water dip will take care of them. You may have to repeat the process again to get all of them. Good luck.

[beach]

thanks blue ocean diver for the response.man how did you find that little thing.my problem is the tanks that have the buttons that won't open the zoos are attached to the rock.i do have two frags that are going to bath in fresh water in a few minutes.once again thanks for the tip.beach