How the filter works?

[iheartbettas]

i've always thought sponge filters were a bit unsightly, so I'd go with this little guy if you had a 5 gallon. http://www.drsfostersmith.com/product/prod_display.cfm?c=3578+3579+9821&pcatid=9821

If you decided on a 10 gallon,then you could use the smallest aquaclear filter. AC20.

 

[iJohno]

Thanks for the tips, I upgraded my 2.5 to another 10g and kept the 2.5 as a hospital tank for my betta .