I have multiple species of Tortoises. All knock on wood have been doing fantastic. Up until we bought Golden Greek Tortoises. I bought two. All of a sudden the underbelly on the one started turning light black and then his belly and his shell got really soft. The black got worse and this is all while still eating well and he just passed. Nobody could tell me what was wrong. Now my last one has developed the same as the other and it’s spreading just as fast as the last. I tested the heat, cleaned the cage, changed food types(everything given is organic), bottled water not even tap and there still having problems. I give calcium and just started vitamins. I’ve included a belly pic of my last one left if anybody has any ideas it would be greatly appreciated. Can’t get in the vet till Monday but with as fast as this travels just taking a shot. Thanks