HELP!!! Zoo's Dieing

[tippmann03]

Almost all of my zoanthids have begun dieing in my tank, and i cannot seem find the cause. It started about 2 weeks ago with the polyps closing on one of my colonies. since then, all of my zoanthid, near a dozen or so, colonies are closed up or are startin to close up and not open anymore. The ones that closed first have deteriated to where thet are starting to break down. Nothing else in the tank (LPS and Sofites) are showing any signs of death or anything like the zoanthids are. If you have any idea what is causing this, i would appreciate a speedy response. Any type of trouble shooting tips to help me find the problem would also be very welcome.

So far i have checked my water levels, replaced the carbon in my cartrage filter, and done a 20% water change. (I dont a 10% change weekly)

Water Levels: Ammonia: 0, Nitrite: 0, Nitrate: 0, Phosphate: 0, Alkalinity: 6.2dkh, Calcium: 400, PH: 8.2, Specific Gravity: 1.024

I hope i someone can help me because not only do i have quite a bit of money sunk into these colonies, but the zoanthids are my favorite corals and i would hate to lost them all.

 

[Anonymous]

You may have predatory snails in your tank. Heliacus snails consume zoanthids. Sometimes dead or dying sponges will kill them off.

All of these could also contribute to a bacterial infection, which will cause them to melt away.

 

[Len]

I have had zoanthid patches die off for reasons I still can't figure out to this day. Zoanthids elsewhere in the tank continued to thrive whereas a certain patch would die off. I believe there was some local toxicity, but I haven't been able to diagnose what it is. Is your zoanthids dying across the tank, or only in select areas (assuming you have multiple colonies)?

 

[tippmann03]

I've checked for snails, and the die off was in all parts of the tank.

but i think i've figured it out now...i recalibrated my refractometer and it turns out that the salinity was way way to high. I had figured that you only had to calibrate it once and it would be set, but i guess i'll do it more often from now on. Hopefully the colonies will begin to come back now.

 

[jwc3]

Did you ever figure-out the cause of the die-off? Did adjusting your specific gravity help? I have some zoanthids that have recently closed, too. Thanks.

 

[SnowManSnow]

super high salinity would do it...

get that salt under control!!

Good luck!

b

 

[Tackett]

kinda curious about this myself...been watching for a reply from him.

 

[tippmann03]

ya salinity was the problem initally, most of the colonies came back after that, however, i am fighting nudibranch now. i dont know if it began at the same time as my high salinity, or whether they poped up shortly there after I noticed a few of these small jelly like things, some the size of a pencil eraser, others the size of a pin head, moving slowing around on the zoo's. They are called aeloid nudibranch, or something to that extent, and they feed on the surface of the zoanthids. they dont actually damage the zoo' themself since they are so small, but if there is one on a colony then any zoo near it will not open up. They must have come into the tank on some zoo's i purchased or something, and i did not notice. I removed a dozen or so initally, but they are so small and can really be anywhere, so i never get them all. and every week i end up removing a dozen or so more over the course of the week with a turkey baister. As far as i know there is nothing to do but to manually remove them, and it looks like i will be doing this indefinitly.