I purchased a Wyoming white clown last week. It had always eaten well. I purchased a companion but it has not eaten. When I introduced it to the tank the original ran over an made a quick pas at it but then they paired up and have more or less swam in unison since then. the new addition would watch the one eat but not join in. now they are both not eating and the first fish had a heads up attitude this morning and seems lethargic. I put an air stone in to help oxygenate the tank but am hoping that it is not on a down hill health spiral. when asking the shop where it was purchased if there was any special food they were accustomed to they asked if it was swimming in that fashion as if it meant something but at that time there were not - just not eating. Any help would be greatly appreciated.