Betta in a Community Tank
We have a 25 gallon tank, that is just slightly wider than it is tall. We added some crypts and java ferns, then added 6 neon tetras while we were waiting for a shipment of plants ( water sprite, hygrophilla agustopholia, and micro sword ). The new plants were planted upon arrival and two weeks later we moved a full size male betta from the quarantine tank. The neons love him and follow him all over. The betta ignores the neons, but he does zoom over and flare up at some of the snails that must have hitchhiked in on the plants ( though we have never seen him eat a snail ). The neons are actually much more aggressive at feeding time and the betta never seems to mind this, but lets them eat their fill. The one thing that hasn't worked out is that we thought the betta would stay at the top of the tank, the neons, in the middle, and that we would have corys for the bottom level. Our betta loves the plants so much that he is most often playing down in the middle and bottom of the tank in the plants. I have heard of people with aggressive bettas though. It might be a good idea to have a 5g or 8g tank available to remove the betta to if they are aggressive, introduce the betta after the other fish have claimed the tank, have a small plastic colender to place over the betta until he settles in, and make sure there are lots of plants , rock caves, or stumps for fish to hide in. We have been lucky and our betta didn't require any of the precautions, but always better to be prepared.