So there's this local shop around me that uses only sponge/spiral filters with power heads through out all of their tanks, even the 500 gallon! So I decided to give it a shot on my 180 gallon, I only spent about 60 bucks and it seems to be doing its job, I've never had any problems (knock on wood). It's about a 2ft long sponge/spiral and the top just connects to a power head shooting back through the tank. I need to get another one for more filtration but I was just curious if anyone else has used this kind of filter?