Who eats ricordea and zoo's

[cag]

I have had my reef tank growing and developing for three years. It has gone through several upgrades to bigger systems, and I made a move last fall to a 90 gallon system. At that time I added a bunch more rock, but was carefull to put in only rock that had aged at least 4 months, so the system didn't seem to cycle that much. But ever since thankgiving my beautifull collection of zoos and ricordea have been shrinking back and then dissappearing. I have watched day and night for offenders, but have only seen one long worm, slim and smooth that retreats from light grazing once near the base of a coral. Here is a list of what I know is in there, does anyone know if I have been missinformed on something from this list. As far as I know nothing here is a problem.

Fish
Yellow Tang,Purple Tang, Sailfin Tang, Regal Tang,Timini Tang, Clown Tang, and Powder Brown Tang. 2 Chromis, 2 red blue strip damsels (new), a cleaner wr**** a six line wrass (new),2 maroon clowns, 1 ocelaris clown, 2 yellow watchman, 2 orchid fridmani, and one small batfish.

Inverts
4 cleaner shrimp, 3 pepermint shrimp, 1 fire shrimp, 2 dappel shrimp, 1 mini coral banded (purple body, yellow, white , red striped legs), and one tiger prawn (ornate looking patterns almonst like a mandarin dragonette, but in tans and golds. He is shy, only comes out at night, and has filter feeding front legs). There is also a Sea Hare, a cucumber, astria snails, pyramid snails, about a dozen zebra hermit crabs, 5 boxer crabs, 3 red footed snails (they do have a spike on the front of thier shell, but I have never seen them attack a coral.) a red formosia starfish, a blue leathery speckeled starfish (that I have had from the begginging so I know it is safe), some feather worms, and serveral bubble tip anenomies.

Coral
finger leather, 4 kinds of star polys, 3 ricordea left from the original 12, 10 zoos left from the original 16. one favia, 3 other mushrooms, 3 different trumpet corals, a torch, elepant ear, and 2 sps corals.

My water has been fairly stable. Skimmer works fine. Ph 8.2, calcium between 380-420, temp 81, KH good, nitrate up a bit at 12-15 (but manged), no nitrite or amonia.

The corals look awesome, then one day the zoos will not open, and then over a few days to a week the colony dissappears. The ricordea do the same, they shrink, loose color, look damaged or mushy, and then they are gone. It seems to effect only a couple at a time, others look fine, till it is their turn. I bought the six line hoping he would eat any small offenders. Any ideas would be greatly appreciated.

[cag]

found little tiny snails last night. They have a checkered pattern in them, and they seem to come out mostly at night. I pulled about 30 of them out last night. Could these be the problem? They weren't actually on any coral, just the rocks.

[Delphinus]

Can you post a picture of the snails? It sounds vaguely like a snail I have in my cube tank, in which I've been unable to keep any kind of coral in the last 6-8 months because they just disappear. However I thought it was the crabs that are in there (I have like 8 or 9 hitchhiker crabs, they're too fast to be caught .. )

Anyhow, crabs and some cowries aren't necessarily innocent either. You might have crabs in that tank and not know it, it took me 6 months after buying the rock before I started seeing them come out regularly. The thing that annoys me the most is that I inspected each and every rock closely for crabs in holes before putting it in the tank ... they were obviously very deep inside or maybe they were larval and somehow survived the shipping.

[prodogg02]

if it has checkered patern it is a sundial snail they are a type of trap door snail.they are zoo eaters they are very bad read up on them awhile ago will post site name if i can find it http://www.thesea.org/reef_aquarium/...sts_snails.php

[Julian G.]

Is this: http://www.oregonreef.com/sub_worm.htm What that worm looked like? If so, then as it's says in the link, there's your problem!

[cag]

Followed the instructions, it still doesn't pull the picture into the thread. Not sure what I am doing wrong. Sorry.

How do you get rid of these, if they are the enimy. They are small and hard to get out by hand.

[danny zubot]

I just sort of went over the same things in a different thread. Check this sight to see if you can find any culprits.

http://www.zoaid.com/index.php?modul...&g2_itemId=384

[cag]

Thanks for the replies. To answer the behavior question. The tangs actually get along quite well. Everyone is fat and happy, and there is very little argueing. The occasional showing off and posturing, but nothing that turns into problems. Between a good skimmer and doing a 10% per week water change, the water perameters are usually pretty good. So i think there is something in there snacking at night. The snails look just like the good ones from your suggestions, so it isn't them. There is one worm creature I have seen a couple of times that might be like one of your suggestions. I will watch for it closely. Thanks again for the help.

[cag]

I have seen some strange brownish redish flakey sort of small leaf-like things growing on the rock lately, and now some seem to be on zoo's that don't open. Has anyone ever heard of this before?

[albert_dao]

Sounds like flatworms.