The reason I ask is that I have never lost any of my three sterbai or three axelrod corys and yet I have lost four of six of my pandas in the exact same tank. I keep all of my corys together and have had the axelrods for almost as long as my pandas. The axelrods have grown considerably and so have my two surviving pandas but losing four of six makes me think they're a more fragile fish. Anyone else experienced this?