Now see, I have a betta in with 6 platys. The reason your introduction did not work, is because you introduced the platys into the betta's territory. With mine, I had the platy in there, and then added the betta. Therefore, territory is not in the aggressor's spot.
Plus, it also depends on your betta. Some bettas are just plain mean... Others will chase for a couple minutes, then mind their own business. Some do not even bother with the other fish - other than maybe checking them out.
In total my bettas have been with the following with zero problems: guppies, platys, blind cave tetras, skirted tetras, zebra danios, dwarf african frog, apple snail, platys, balloon mollies, balloon molly fry, platy fry, regular molly... I have 4 males and a female, and all of them I trust in a community tank other than Dusk, who is a definite bully. I also make sure the other fish are not aggressive or fin nippers... Some platys nip (mine were younger and learned fast) others not.
Compatability depends on the attitude of all fish, especially the personality of the betta :)
Breed for the breed, not for the money; the words any REAL breeder would understand.
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