Who Gives A Fish Forums

There are indeed wild types of dwarf bettas that occur naturally. The ones we commonly come across can vary significantly in size, just like people do. We have a little female betta that is still quite small in comparison to some of our other bettas, which makes me think that it's not entirely ...

If you check out the RSPCA site, it clearly says you've got a responsibility to look after any animal in your care, and that includes fish.

No way, you can't keep them together like that. It's a disaster waiting to happen. I don't know what possessed you to try this, but trust me, it's a terrible idea. You need to separate them ASAP or you'll end up with two badly damaged or dead bettas.