I've experience this similar thing along with others, Such as stress, biting themselves, Fin erosion, etc.
Mind you These were betta's that lived in their tanks for months with zero troubles, then all of a sudden something changes.
I looked at everything, trust me I tried everything, sometimes things would appear better to only get worse or come back with a vengeance,... I've run into this with a few betta's,
Seems some are more touchy then others, (but then so are some of us humans :)
The solution laid in a bigger tank.
I have several Beautiful male betta's here now that if I put in anything less then 5 gallons, in less then 2 weeks they will each have their sets of problem arise again and again..
Tanks less then 5 gallons just aren't good enough for some betta's.
I can't help but wonder if that alone is why some people are never able to cure/heal/help their betta's get better.
Small tanks are not betta friendly, They just learn to survive in them & Many don't and problems keep arising, Water changes can only do so much, It Comes to a point with some betta's that this is just not enough.
Last edited by Chicklet; 03-26-2010 at 10:30 AM.