I'm about to rescape my tank and want to do a quality job with the substrate. I've got bags of ADA Amazonia (original) ready to go but was considering what to put under them. I've got access to pumice, but was wondering about adding supplements to it to make something similar to a DIY powersand. Does anyone have any comments on adding things like KNO3, KH2PO4, K2SO4, iron and trace elements to a pumice layer? What about Mg and Ca? I've also got access to plenty of worm castings and iron rich clay.