common causes of zoo's not opening?

[gotbags-10]

So yeah i have about 10 different zoo frags in my aquapod 24. Stock 2x32 pc lights. They were all added over the course of a couple weeks. Have had them for about 3 months now. I've had no growth at all but they have all been open and looked healthy thus far untill the last two weeks. One by one they've all been closing except for a few. I've done some water changes and monitored my params which all seem to be fine. amon, nitrite 0ppm nitrate at around 5ppm calcium at 400 alk at 8 ph is 8 salinity 1.024. My temp has been a little high recently at 82 because of the heat so i unplugged my heater and keep the lid open so now it stays at about 76-78. The only thing i have in my tank is a false perc clown an emerald crab small bristle star, coral banded shrimp usual hermit crabs and snails. i will say the bristle star i found in a small piece of live rock that i just got a little before it started but i don't think its bothering them at all. I've let it go over the last two weeks thinking they would come back around but nothing yet. Just wondering if anyone could weigh in on possible causes.

 

[LoudProudNPunk]

it could be nudi branches. Dip your frags in RO water heated to right temp and ph set for around 4-5 minutes. Then shake them around in there and see if nudibranches fall off. Or it could be fungus, when your polpys close does there appear to be any fungus growing on the mat or stocks?

 

[gotbags-10]

i don't see any fungus growing on them but not real sure what to look for. As far as dipping them i've seen threads on here about using different stuff like lugols for example. Would using that be worth it or just do it in ro water? And also how would i bring the ro water up to proper ph?

 

[Aearon]

Do they open after changing water?

I'd found the same problem. At first I try to find predators or others irritate but nothing be found. The water parameters seem fine (temp 28-29 celcius, pH 8.3, kH 8, nitrite 0, nitrate and phosphate less than 5 ppm others parameter is not measured)

I try to replace some water, some looked a little better so I decide to move them to my oldest and more stable tank, all of them became opening within a day!!!

If zoas don't have the symptom of being prey, irritate or infecting, I guess it's the water problem.

 

[dorian965]

how old are your lights?
mine seem to close up after the bulbs are getting old or sometimes you just need to run carbon. is your tank very crowded?