Brittle Star Pieces

[pwisecup]

My Brittle Star has been in my tank for about 4 months with no problems. I have 4 Blue Damsels and 4 Clowns, 3 mini-Horseshoe Crabs. Everything seemed fine last night around 9 o'clock. The star was sitting on and around a piece of live rock. When I checked the tank at about 10:30, the star was nowhere to be seen (disc), but there were tiny bits of tentacles (legs or whatever you call them) all over the substrate below the rock and some pieces were on the rock. One piece appeared to be kind of sticking into a hole in the rock. I still haven't found the star. Does anybody know what this sounds like? I am not sure if he's dead, or just lost a leg and is hiding. What would have made his leg go to pieces like that? I know I don't know much about aquariums, but this seems a little strange.

 

[flydan]

Hey,
Brittle stars can lose one or more legs and survive. (They grow back.) I don't see anything in your list of critters that would tear into a brittle star. Sorry I'm not more help.
Bump:joy:
Dan'l

 

[arjayl]

Ive seen one litterally break apart...YEARS AGO. Someone on this board suggested water quality which I believe was acurate. What are the numbers for your water?

 

[ocellaris_keeper]

If the star died your horseshoe crabs got to work by devouring the thing!! this is what keeps the ammonia level down with a cleaning crew.
OR
you have a sneaky critter that came into your tank with your Live Rock. I had a pistol shrimp that killed:
2 Cleaner shrimp
1 star fish (exactly as you described)
2 hermit crabs before I got that thing out of my tank
Hope this helps

 

[pwisecup]

I found him! He is nothing more than a disc with tiny stubs for his "legs". He is still moving around, but obviously is not as agile as he was previously. There are Bristle Worms cleaning up the remains of his legs. Could they have attacked him? They are quite large bristle worms. I can't seem to find a lot on bristle worms and how they act. Any help here?
For the question about my numbers: I tested the water on Sunday afternoon and amonia and nitrites were at zero. Ph at 8.2. Only thing off was nitrates at 20 ppm. I did a 10 gallon water change (55 gallon tank) and have water made up to do another 10 gallon change tomorrow night. I checked the nitrates after the water change on Sunday and it was still at 20 ppm. I will check everything in just a minute to try to figure out what happened to my brittle star, poor guy.

 

[elfdoctors]

How about your specific gravity? How are you measuring this?
Sea stars want this to be closely regulated between 1.023-1.025. They will show signs of problems much sooner then fish. They lose legs as a sign of stress.
Yours may survive if the central disc appears okay.

 

[pwisecup]

Specific gravity is 1.0235 (halfway between 1.023 and 1.024) on the SeaTest Full Range Specific Gravity Meter.
I just thought about something. I just bought a powerhead. I put it in this past wed (1 week ago). I had it bubbling air at first and then removed the airline, put in the plug and it's just moving the water around. I did this the night before last. Then, last night is when all you know what broke loose with the starfish legs. Could this have caused him stress?

 

[elfdoctors]

Swing arm hydrometers are often inaccurate, particularly after you have been using them for a while. They must be rinsed with freshwater after each use. I would recommend having your water checked with a different method some time soon. An alternative that you could use with that meter is to measure the specific gravity of distilled water. If you find that it is reading wrong, don't make any changes rapidly.
I doubt bristleworms would be causing a problem, particularly if multiple arms were lost at one time.
I doubt that the air from the venturi contributed to this problem. I have not had any problems when mine have been exposed to air.
BTW, Welcome to the Boards!

 

[pwisecup]

Thanks guys for the help! I just checked my numbers. Amonia and Nitrites are still at 0. Nitrates at 20. Ph is still at 8.2. I'll keep in mind about the meter, although I do rinse it every time with fresh water right away and its only 4 months old. I think I'll take a sample of water to my LFS for testing to see if there is a problem I haven't caught.
I really appreciate this forum and everybody who responds or posts their own questions and comments. It's been a big help!