1 male betta, 2 gallon hex, undergravel filter, 50% weekly water changes with stale tap water, gravel, lived for about 7 months
1 male betta, 10 gallon, double sponge filter, 20% weekly water changes with stale tap water, sand, lived for about 2.5 months
1 female betta, 10 gallon, penguin 125, water changes unknown, sand, lived for about 3.5 months
1 male betta, 1 gallon, unfiltered, water changes unknown, marbels, lived for about 4 months
The first two bettas listed were my setups. The last two were my brother's and his wifes. All were kept in the same tap water. All were feed different foods. And they were not all bought from the same store. Two developed large growths at there neck area. The other two become stiff and they couldn't move.
Any help would be great. I would really like to get another betta, but I want it to live more than 7 months.