Best filter for 2.5 gal tank

[Tashaj46]

I have a 2.5 gal tank that will hold 1 betta and maybe a snail. I am looking for advice on the best filter for the tank. The tank came with a filter but it is very strong and there is no way I change that.

Any suggestions?

[waterdog]

I use a sponge filter in my 2.5. You can put a control knob on the airline and have a gentle bubble flow that doesn't effect the entire surface.