I currently have the little plastic black balls in my canister filter. (Marineland c series) They are super annoying when I'm cleaning because they float. I also have a tray that has ceramic cylinders. It's the original media the filter came with. Is there something I can use instead of the black spheres that won't have the same issue? Or should I fill the other tray with ceramic rings too? Or just anything else that would be better or that I should add to the media the filter came with in general?
Also, if I get something different is it okay to replace the one tray of media when I replace the carbon without messing up my cycle?