scorpion-like creature in tank

Question
For about 2 years, I have had a 20 gal tank with swordtails,  guppies, and a algae eater.  The only new thing I've added is floating moss - and that was about 3 months ago.  Today I noticed a strange bug or something on the bottom of the tank.  It's less than 1/4" long, and looks like a ghost shrimp, but it's tail curls up like a scorpion, and splits into 3 sections.  It's awful - I can hardly look at it.  I was vacuuming the tank and found 2 of them. There could be more, I'll keep looking.  Thanks, Kate.  p.s. if you go to a letter from 4/3/05 to Nick Kochelek, from "Becky", you will find a better description.

Answer
This is very strange, I have never had this big of a bug in my tanks. I have only had tiny white bugs on the glass, which are not bad just ugly. I can imagine it is not nice to look at. I would guess this bug came in the moss. I would suggest going to the place you got the moss, unless it was a chain store, and asking them about it. I would only guess it could be a baby shrimp but again I have never had one of these. I only know of harmful bugs in saltwater tanks. My best guess would be a baby shrimp. If they are shrimp, it is not a problem and perhaps even good to clean. I would recommend going to the place where you got the moss and asking them. If that does not work, I would recommend asking another expert. I am sorry I cannot help any more. I hope you will find it out. Let me know if you need anything else.