Alternatives to mechanical filtration?

[d3rryc]

Hey, there!

First of all, GREAT article - thanks for sharing the knowledge. However, you made the comment that you don't use mechanical filtration of any kind. I got rid of the bio balls in my bubble tower b/c they would get covered with DOCs and were contributing to red slime in my tank. I noticed in your video showing a bubble tower that you have rock rubble in yours. How do you manage the buildup of DOCs in and on the rubble without using a mechanical filter of some kind? I'd love to stop messing with the socks I'm using on my drain line, but I don't know of another way of stopping the DOC buildup.

Help!
Derry