i found these wooden air stones that are cheap, but the people who left comments on petco comments section said that some black slimy stuff was gettin on it, will this not happen to me cause im not using it for a fish tank. heres the product in case i didnt give good info:
http://www.petco.com/product/9488/Red-Sea-Berlin-Air-Stones.aspx?CoreCat=OnSiteSearch
http://www.petco.com/product/9488/Red-Sea-Berlin-Air-Stones.aspx?CoreCat=OnSiteSearch