My Bettas are all flourishing wonderfully, they've been extremely healthy, and I even saved one of them from finrot he had when i bought him.
Do their fins ever stop growing though? I mean... this is a picture of my oldest Betta 'Pops' and he's about 1 year and a half old. His fins are extremely long! It's hard to tell but they almost drag across the bottom of the tank as he swims. Is there a point that they will become an inconvenience to him?