HELP! Unidentified Sea Critters!

[nickbuol]

I have some new live rock (cured for 3 weeks at my LFS) in a large tub. I am using it to seed some southdown sand for a live sand bed. Anyway, last night, I noticed some odd creatures on the rock. I can't describe them, but I put some snapshots up on a web site. If anyone can identifiy them, and let me know if they are good or bad that would be great.
The website (I hope that this works) is: http://www.geocities.com/nickbuol/USC
Thanks everyone!

 

[burnnspy]

The tubes prolly belong to a type of tube worm of feather duster and are are harmless.
The little bug is a chiton and is also harmless as far as I know.
BurnNSpy

 

[nickbuol]

I agree with your idea that the one is a chiton. Thanks. From what I am seeing online, they are harmless, but could potentially get farily big (4")...
Now if I could figure out those cylinder shaped things....

 

[nickbuol]

Someone else thought that they might be flatworms......

 

[nickbuol]

On another note, the cylinder shaped things are green, but completely see-through, and don't show any sign of a skeletal structure, or anything. Of course, they are pretty small, but I thought that this might be helpful information.

 

[nickbuol]

I agree about the chiton. After you said that, I looked up "chiton" on the internet and the pictures looked just like it....
The green things DO move around. I keep hearing from people that they are flatworms, but I have yet to see any pictures online of flatworms that look like the things that I have. They do not swim, but move along the surface of the live rock.

 

[billyv]

I have some of the chiton things too. I only see them at night when I check out my tank after lights out. The first time I saw one I freaked....it looked prehistoric, and was near one of my corals. They are wierd snail plated looking things. I don't know what they do or eat, but I don't think I've had any problems from them.

 

[-shawn-]

This first picture is a chiton. These are really cool creatures. As far as I know they are reef safe. I have not seen other wise so far. and nether has anyone I've talked to. I have one that is about an inch long in my tank, and two smaller ones. They can come in very beautiful colors, however they are generally nocturnal. Chiton is related to snails and limpets, and their diet consist mostly of algae and diatoms. Their are over 600 different spieces so it is difficult to say which one yours is.
The second picture looks like flat worms to me. But the description you gave makes me hesitate to jump to that conclusion. Generally flat worms are rather flat not cylindrical. Most flat worms that I have seen that look like the ones you photographed are not good for a tank. They can reproduce quickly and I have seen them ruin show tanks to the point that the tank must be broken down. However, people have over come them. One of the more difficult and expensive ways would to get a nudibranch. There is one nudibranch that eats flatworms, I think it is called a blue line nudi. but I'm not sure. It has a black body with two light blue lines running down it length. These nudibranchs are difficult to come by though; it can take months for some to get a hold of. The other method I have heard to be successful was to siphon out with small airline tubing a hundred or so a day until eventually you have no more left.
I hope this is helpful.