zoas health

[dustin]

Greetings,
Ive been having some issues with the zoas in my tank. Ive got a few varieties that Ive had for a long time, year plus, that all open and are fine. I have some newer zoas, the very small polyp matting ones, that are just fading away. Ive recently added several new varieties of zoas as well, and they arent opening much.

Ive made several changes to my tank in the past month or so, added an ASM GX1 skimmer in the sump (big upgrade from the ole redsea) and have removed about half of my sand bed. Ive also gotten my temp fluctuations under control. My readings are all good except for a low level of nitrates that I cannot seem to kick. Im going to continue to remove the rest of the sandbed as I think this is the cause, I feed very light.

So, the zoas that dont open seem to be retracting their tentacles. They will open a bit, but the tentacles stay contracted? They are all about 10-14 inches below a 175 10K halide, with VHO's running part of the cycle.

Could it be the nitrates? Any one have a similar reaction with the coral 'trying' to open but not fully getting their tentacles out?

Thanks for any advice on this.... I may try and post a pic later today.

Dustin

[leveldrummer]

i wouldnt think zoo's have a problem with low or even high nitrates, they are pretty tough, i would say you light is high, but that deep shouldnt be a problem either, maybe try to move them to some more light, or a little less light, see if they cheer up, all your old ones open fine right? its the new ones that arent doing well? maybe just a little more time and a target feed or two to make them happy would work. sorry, i guess im not much help at all.

[dustin]

Your thinking what Im thinking. I have now moved half the new ones to a lower location in the tank to see if they cheer up.

I also added a large sock of carbon just to be sure no warfare is going on. Im really scratching my head on this one.

[GeorgeW]

I purchased some zoos from a LFS that took about 2+ weeks to finally open. And they haven't fully opened yet. At the store, I was kind of gambling that they were blue, but it turns out they're a bright orange (which is cool too).

I've noticed my zoos do better in the lower light sections of the tank, but I have a 25g (24Lx12Wx20H) with a 250W HQI lamp over top, so "lower light sections" is a relative term.

[xaoss23]

might not be a bad idea to keep a lookout for sundial snails... just to be safe.

[leveldrummer]

Originally Posted by xaoss23

might not be a bad idea to keep a lookout for sundial snails... just to be safe.

good point tony, didnt think of that, im so scared of those things. here is a pic of what to look for

[dustin]

Thanks for the pic, did my work for me. I dont think Ive got these guys however.

Ive moved all my colonies to the sandbed so we will see how they do. Ive also thrown all my larger blue leg crabs in the sump as they had been taking advantage of the feeedings and irritating the zoos. Hopefully they will perk up. I may add some iodine as well.

Thanks for the input.

[Ms. K]

My zoas do that periodically. It almost looks as though the tentacles have been cut off around the edge with a can opener? I'm not sure why they do that, but they heal themselves with time.