I am extremely new to this hobby. I fell in love with the Bangaai Cardinals and ordered 3 from my dealer over two weeks ago. He received them in on a Wednesday (order of 6). I picked my 3 up on Saturday. By Monday, one was hiding from the other two and gulping, hovering off the bottom. He died later that day. Got another replacement and this one went straight to hide. I went online and could only find the articles by Frank M. to look for ideas why the fish were acting the way they were. I did realize that I could have had uneven pairings. I went back and got another one to now increase the numbers to 4. By the next day, one from the original shipment died the same way. Down to three again. When the latest "guy" would venture out, the main "larger" fish would chase him back behind the rock. I concluded I must have 2 males and a female. The one I thought was female was from the original order and had stayed in one spot also during this time. I thought about taking the newcomer who was getting chased back to the dealer and holding until another shipment came in and I could try to pair up better. He died the next day. Then the other one died the next day, and finally two days later, the largest one died. All water tests come back perfect. All other fish doing great. What in the world happened? Any help would be appreciated, because I don't want to give up on having this type of fish