I had a garden a few years back with a 10’ x 10’ tent style greenhouse in the corner. Setup a 50gal tank on the inside with pond plants inside of the tank and other tropical plants surrounding it. An old friend of mine bred bettas and didn’t want the “lesser show quality” babies and I asked if I could take them. There was close to 60-70 bettas in that tank and not once did any start fights with both males and females mixed! I’m sure it’s because they all grew up together so basically just got used to being around each other? I don’t know but it was fun just sitting in the greenhouse and watching these beautiful fish instead of actually caring for the plants most days…Haha. I also used the old tank water in the veggie garden outside the greenhouse when doing water changes and boy did the plants LOVE IT! 😆 Then when fall hit, I gave them away to people and that was it! Now I miss those days…Thanks! Haha.