Hmm. The gouramis might be a bit territorial at this time. Most likely they are attracted to the long fins of the angels. But I would have to say that your fish store was innacurate in telling you these fish would work together. The angel fish are a cichlid and are somewhat aggressive. It seems more likely to me that the angel fish would attack your gourami, but some angels can be pushed around a little if they are smaller. That wont last though. One problem I foresee is, those angels could get up to 6 inches in size each, and they are going to quickly outgrow your 8 gallon tank. Same goes for the catfish, depending on the type. Most cats will grow quite large unless they are of a dwarf variety. The catfish should be able to live with either of the other fish, but the angels and gouramis might be a bad mix. If it is possible, you may want to check with your store and see if you cant trade the angels in for something else that will live more peacefully with your gouramis. Those angels really need a lot of room to swim. With the fish that you have right now, you should really have at least a 30 gallon tank but even then, youll more than likely have issues between the angels and gouramis.