Haha you mean you actually have a tank that doesn't have any pond snails in it? Somehow the pond snails can survive my really soft and acidic water. I had big problems with them in one tank where they came in with some plants.
I have always found bettas to be pickers. If they are curious about something they may try to bite it, and mystery snails are such big, slow-moving targets.
Also depending on the species, you may run into issues with the shell of a mystery snail. A lot of wilds like their water soft, and I know some snails can have issues with this.
Looks like I may have gotten four male honey blue eyes. I can see the darker outline coming in on the fins on two of the smaller ones, and the biggest one I have the photo of is sparring with the males now even though its fins are not as dark. The final one, I am not 100% certain on. It's a bit more passive and I can't really tell whether its fins are showing the black outline or not.
So at this point, it looks like I am going to have to source another couple of females. Unfortunately the store that is selling them at $40 a pair usually wants to sell them as a male/female pair, and not two of the same gender which is frustrating.
I put another piece of wood in their tank to give them some more cover and so far they seem content. They are still glass surfing a bit, but I find schooling fish take longer than bettas and other sort of predatory fish to settle into a new environment.
I think I did get a female rhad though, as the two biggest individuals were flaring at 'her' and each other and displaying a prominent orange/yellow stripe down their backs. I tried to get some photos as they looked good putting on a display, but sadly they move too fast and hate the camera. These were the best photos I could get at the moment and they are not flattering...at all.