I just bought one a week ago, changed his water today and within 3 hours he died tonight!!! I have no idea what happened. When I first got him, he has barely eaten anytime I feed him since day one.
I have had bettas in the past and they always last anywhere from a year to 3 or 4. What did I do wrong? I let the treatment sink into the water, not cold not hot, room temp, sadly I only had a 1/2 gallon tank... usually I have a 1 gl.
To the OP, are all your bettas in different tanks? Can I see a full pic of their living environment?