Aaron's had this gold assessor since last year that has always swum upside down. I've been in the store at least every weekend for water and have never seen that fish in any orientation but upside down. I finally decided to buy him yesterday and brought him home; he hid in a cave for about an hour and came out, friendly as can be and totally unphased by people outside the tank... and right-side up. My defective fish is defective! (I had a feeling this would happen.)