LadyDragon
Fish Fanatic
I have kept Bettas in with platys but personally I think the activity of a tropical community adds stress to the betta. The betta ended up with Ich while in the community. I removed him and treated both tanks. The betta is doing well, but I feel that a community lifestyle was too much for him.
My black HM male, Gothie, had a similar experience. He didn't get sick, but he did become very shy and reclusive after his experience in a community tank. He sort of had PTSD or something... He has never been BOLD or OUTGOING since... He was a very excitable boy before, now he is definitely a shy and passive personality.