I was about to add laterite to my tank when I realized it has TONS of mulm in it and I was wondering about siphoning out the mulm. Then I asked myself, if the mulm has such a high CEC, why not just add a bunch of iron and let it bind to the cationic sites on the mulm? Am I missing something here? Dave Dave Gomberg, Experimenta San Francisco CA USA gomberg at wcf_com