Activated carbon binds stuff pretty well. I don't have any references but I suspect that it would have a hard time giving giving phosphate back. Why not change the carbon, or just pull it out, and see if things improve? I haven't run carbon in my tanks in forever. But then again, you are talking to the guy who lets his silver dollars eat all his plants, so what do I know? :) On Wed, Dec 2, 2009 at 4:21 PM, Jeff <jeff@gotperk.com> wrote: > My amazon swords have some of their leaves covered in a dark colored slime; > could this be caused by too high of a phosphate level? I don't have a > phosphate test kit yet to check the level; Thanks, Jeff. > > > > > > > > _______________________________________________ > GSAS-Member mailing list > GSAS-Member@thekrib.com > http://lists.thekrib.com/mailman/listinfo/gsas-member > _______________________________________________ GSAS-Member mailing list GSAS-Member@thekrib.com http://lists.thekrib.com/mailman/listinfo/gsas-member