What do you think would be the best filter for a Betta bowl (1-2g)? I would get a larger tank but I live in a small apartment so a bowl will have to do! Or do I need a filter? I've read it's easy to overpower the bettas. Thanks guys
Even a 3 gallon would work, a lot of people have bettas in 3g on here, 1 more gallon would make all the difference for him without taking up much more room for you. Yes, you need a filter. You can always use a baffle if the flow is too strong. As for what kind of filter I can't recommend any as I don't have anything smaller than a 5g here and I use the Aquatech 5-15 for my 5g (with a baffle for my betta).
If your LFS carries Deep Blue brand, they make some very tiny micro filters for small tanks. They actually have HOB filters smaller than any whisper ive even seen. I think the smaller whispers do have adjustable flow on the internally powered models, and then the super small ones are solely air driven. I actually have and use 4 different styles of whisper filters, they are very quiet and decent filters. However in a smaller tank, they may take up much needed space. As others have said, if you can go at least 3 gallons, it would be much better. A 5g though really isnt big at all as far as how much space it takes up, and youll have a much happier and healthier betta. Also the larger the tank, the more stable your water parameters will be.