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Aquarium Advice Regular
Dec 7, 2004
Asheville, NC
Sorry I don't have a pic, but my camera is being difficult and wont work for me. I have identified most of the critters on my rock, but I do have a couple of questions...

1. Small crab hanging upside down in one of the caves I constructed. He appears to have translucent fan like structures coming off of two apendages that he sweeps into his mouth like he is filter feeding. I assume if he is filter feeding, he shouldn't be a problem. Anyone know what he is?

2. Reddish-orange coral looking. About 1/2 inch wide with 2 openings, one of each side. I have two of these, one of which looks as if it is dying as the outside is losing all of its color. The other is doing great.

3. I have a Christmas Tree Worm. From what I've read, they are difficult to keep becuase you have to keep the coral that it is attached to alive. What does it need from me to stay alive?

4. Dieoff. How much die off should I expect? I'm seeing lots of little patches of white. Starting to grow some halimeda, which is good.

5. Cone shell snail. I understand he is a nasty guy that I don't want to keep around. Is that right?

You guys were so right about the rock. It is beautiful. Lots of colors and we got brittle stars, urchins and lots of anemones. I know the anemones may be a problem soon, but we're going to hang on to them for the time-being. The kids love them. I'm sure I'll think of more questions soon. If I can get my camera working I'm going to try to keep a photo log of our progress. TIA for any help identifying my hitch hikers!

1. porcelain crab (this is about the only safe crab you can have)
2. Hmm, could be a stoney coral or a tunicate. Is it hard or soft to the touch?
3. It's a filter feeder. I've read that they need their host coral to survive but, I've also seen them growing on rock so, I'm not sure. If that's the case then there isn't much you can do. Fan worms in general will filter the water for food and don't really require feeding.
4. Die off should be minimal. Use a turkey baster to clean the rocks and keep good water movement.
5. Not all cone shaped snails are bad. Cerith snails (good) are coned shaped but, without a pic, can't really say which one you have.
Should have been more discriptive with the snail. It is grayish in color, about 1/4 inch long. It has a tube that sticks out in front and "feels" around as it moves.
Coral is soft to the touch and the shape makes me think of a pillow. Kind of rectangular shape, but rounded on the top and the two spouts are at what would be the corners of a pillow. Hope that makes sense.
That would be a tunicate. I just got 20lbs of rock from and it came with lots of these on it. Alot of snails have the tube. Especially the nassarius species. I wouldn't condemn it just yet. I'd watch and see.
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