Thanks for the comments rebelprettyboy, So i have a question. When i remove my bio balls and sponge thing, how much lr rubble do i had ? Do i completely fill it up to the top of the chamber ? I mean all i have in my jbj nano cube right now is whatever it came with. A black sponge and thats all i ever pull out and clean every week. I think maybe something is underneath it. And then i have filter floss over that i change every week. Now in my aquapod i have bioballs and a blue sponge that i rinse out with tank water when i change the water every week. So i take all that stuff out the chambers and fill it up completely with just lr rubble and then put filter floss over the top of that ?