Hello! After the death of one of my bettas, I’m looking for a new inhabitant for his half of the divided 10 gallon tank that he lived in. Throughout my fish’s life he lived in 5 gallons of water, cycled, heated, and filled with live plants. The conditions were practically perfect. However, he was always sick and as soon as one disease went away he’d have a case of fin rot or popeye or some other issue. On the other hand, my female betta who shared the same tank and was thus exposed to the same bacteria in the water and also shared the same water parameters, has never gotten sick or showed any sort of symptom of sickness or discomfort. I’m beginning to think that my male betta (the one who died) had some sort of genetic issue. He was a blue halfmoon butterfly betta from Petco whereas my female was a red halfmoon female from PetSmart. Do you think my bettas problems were related to genetics at all? And if it is how can I avoid this again? Are certain colors, tail types, or genders related to poor immune systems, or is just a luck of the draw sort of thing?