12 Foam Filter Pad Inserts for Hagen Fluval 404 / 405 (A-226)
Replacement foam inserts for Fluval 404 / 405 / 406. These foam pads provide mechanical straining of particulate waste. They prevent particulate waste from prematurely clogging other filter media in the module stack. Although the primary purpose of the foam pad is mechanical filtration, biological activity will eventually occur within its pore structure.