My soon to be Dwarf Puffer tank is finished cycling. 0-0- and about 90ppm of nitrates. Took 6 weeks to cycle. I took out my media and set it in the bucket that I'm draining 90% of my water into. As I took the media out, I noticed all three layers (AC20 - 10g tank) where filthy. My 29g wasn't this bad. My question is, should I replace the sponge, carbon, or rock? It's so nasty my bucket with the media in it is layered with brown flake like stuff. (Idk the proper name) should I replace 1 layer or just rinse it all off in the filtered water?