help me make a filter

[aprime11b]

hey I just bought a acrylic tank with a built in overflow in the middle. it has one hole at the bottom of the overflow box thing. I dont know what to do with it because I never had one before. Should I use it or what. Can you please help me build a filter. Im open to ideas but somewhat simple but efficient. thanks

 

[pjsmetana]

http://www.monsterfishkeepers.com/forums/showthread.php?t=362172

Enjoy