PlanetCatfish.com

so then what do i do about the carbon? lol. like what do i replace it with? because the filter already has a set of 4 sponges, then the blue spikey balls and then the white cylinder rocks, then the last level is the carbon. although the other filter has no spikey balls and two layers of white cylinder rocks.

It really depends on the place where you put the carbon. I generally replace the carbon with an equivalent amount of sponge (in my TetraTec Ex series filters, I've just removed the carbon bags, leaving the space empty, since the water still has to take the same route either way).

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Mats

hmm alrite