forgot to ask him about ammoniafish_4_all said:Well it could be a couple things. The first could be an unhealthy fish form the LFS. The second would be too short of an acclimation period and the one that is sulking is having a hard time adjusting. Do you add any tank water ot the bag before adding them to the tank? Also, what are the tank paramemters, most important are pH, nitrites and nitrates. If you can test for them let us know the numbers.
Are there any other fish in the tank and has it been cycled?