Zoas small/not opening

I purchased two zoa colonies about 2.5 weeks ago. One is doing great, but the other hasn't opened yet. The LFS guy said it was a relatively new colony, but I should expect to see them open by now! The parameters are fine- everything else in the aquarium is doing good and is growing. I found a sundial snail on the rock about a week ago and removed it. I also did a FW dip on the coral a few days ago to get rid of anything else. It looks as though the tip is starting to decay? With a few polyps falling off over the past week, however, the rest of the colony looks fine.

Any suggestions?

Oooh, you are right, those are not looking to good. :( Is it just the photo or are they covered in some sort of a white fuzz?

What are your water parameters and where in the tank are the zoas placed?

and whatever is in the back looks bad. Ive seen pics of that white fuzz on em before and seems like they go downhill after. forget what it is though.
was it on there when u bought it? if so take it back
i actually had a fish store guy tell me the apitasia on the rock is good not a pest. Yea havent gone back to that place.

well- maybe the photos aren't as clear as they should- in reality, there is no white fuzz on them (fungus) but the tip is black and the polyps are starting to die off. I have since done a water test and found my nitrates are way too high... in the process of doing some emergency water changes in the next few days- funny, since none of my other tank inhabitants have eluded to any problems with the h20 quality.

zoas are typicallly the first to show any symptoms of water quality problems in my tank.