Crayfish shouldn't be kept with any fish you don't want to lose, and especially not a slow swimmer with flowing fins like a betta.
BTW, kuhli loaches really like being in groups. I'd recommend having at least half a dozen in order to bring out their true personality.
I don't think you'll find any snail eating fish that won't wipe out the population. Its not like the fish will eat some and then stop and think, gee, maybe I better not eat them all.
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Tina
Puffers:
Auriglobus silus x2
Colomesus asellus x1
Tetraodon travancoricus x1
Tetraodon biocellatus x2
Tetraodon nigroviridis x1
Tetraodon baileyi x2
Tetraodon lineatus x1
Tetraodon palembangensis x1
The greatness of a nation and its moral progress can be judged by the way in which its animals are treated. - Mohandas Gandhi
