It's ok, you're doing your best now and that's what is important. It's possible to keep them together but as you already know they should be in a much bigger tank. Some minnow tetras like that are kind of nippy, it depends on the personality of your betta. Returning the clouds might be a good idea, yeah. There is lots of bad info on bettas out there, and as an aggressive species they often do best solitary. Female bettas can be kept together under certain circumstances. But no, bettas don't need friends the way say like, rats or goldfish do best with companionship. Just keep doing research, clean water is most important. If you can keep the water clean while they're all together it'll be ok. Feel free to PM me with any questions.
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