You can also buy a breeder cage from a petstore for about $6. The one I have has slits in the sides for water flow to pass through, and also floats on the surface of the water.
Freshbrew, I didn't see it mentioned anywhere, but how did you acclimate the fish? Many times when a new fish shows those signs after being healthy at the LFS, it's due to improper acclimation. I always recommend the drip method...it takes time, but ensures a healthy fish.