I am very upset i bought beautiful betta yesterday,he looked perfectly fine. He ate ,swim no symptoms at all. I bought him for girl who has 5 bettas. She called me today saying betta is dead. I can not imagine why. He was also active and health looking.and she know how to take care of them because she already has 5. Her last betta died that why i bought her this one. And i asked her disinfect the tank. I thinking may be she didn't wash well the tank from soap. I had betta died before and i disinfect with sanitazer and soap and windex but i washed it very good. And my next fish was ok.