I've used pollyfill factory carts 
Sponges
Fluval
Lipton Pyramid Tea Bags
Blue Foam
and now I am trying cotton
Is there a reason people don't use plain old cotton?
I didn't use no spring or straw, I just rolled up a round piece and stuck it in a full cart and it's working perfect. So what if you have to stick another piece in on refills its too easy. And i'm not even sure you have to as I am just tring this now for the first time. I find it hard to believe nobody has done this being as it is sooooooooo cheap and easy. So I am asking..
Has anyone tried plain old cotton?
Sponges
Fluval
Lipton Pyramid Tea Bags
Blue Foam

and now I am trying cotton
Is there a reason people don't use plain old cotton?
I didn't use no spring or straw, I just rolled up a round piece and stuck it in a full cart and it's working perfect. So what if you have to stick another piece in on refills its too easy. And i'm not even sure you have to as I am just tring this now for the first time. I find it hard to believe nobody has done this being as it is sooooooooo cheap and easy. So I am asking..
Has anyone tried plain old cotton?