I recently bought 3 new rays about a week ago , I cant seem to get them to eat , I am trying to feed them frozen krill (shrimp) but they dont seem to be taking to it the guys at LFS said that is what they were eating and ghost shrimp I am going to try ghost shrimp tonight but why will they not eat ? I am getting worried , could it just be because of the transfer to my house and they are not comfortable in there new tank yet ?