Coldwater Plec

Question
Hi there, Just seen this website whilst trying to solve a query.  We have today just bought 2 Coldwater plecs and 2 fantail goldfish.
Got them home and 3 are as happy as larry but one of the Flec's is just st at the bottom of the tank doing nothing.  He is breathing and clinging to a pebble but will not move otherwise.  He floated to the bottom of the tank of his back and made no movement, he is definately alive and was swimming around in the tank a the shop.  Any ideas on what the cause could be? Stress, shock? How can I solve this?
Many thanks for your time
Best regards
Jason

Answer
It could be shock. Did you acclimatize the fish to the water temperature before added them (you put them with their bag in the water and let them get used to the temperature that was)? Perhaps your water quality is different from the pet store's. I doubt this is sickness but keep an eye on him all the same. If he doesn't show signs of improvement, move him to another tank and tell me if he shows any other signs of sickness.