Cation exchange capacity & Anion Exchange capacity
a high CEC promotes nutrient retention in soils, and i'm assuming the same is true in aquarium substrates (of value for planted tanks)
some nutrients are not retained in such soils due to their inherent negative charges
(sulphate, phosphates, nitrates)
AEC have a tendency to attract these
while i'm reading up on it now, i'm curious if others have information and/or experience on the subject of using minerals with either high CEC and/or AEC
although i'm finding that minerals that exhibit AEC primarily only exhibit AEC in highly acidic conditions, ... except for oxides it seems.
rings me to two questions.
mixing a high CEC mineral into the substrate with adding AEC minerals/oxides, ... would the substrate retain both positive & negative nutrients ?, would they cancel each other out (bind with each other) and be neutralized ?
in the case of oxides, ... (still looking for various types) would that be particularly safe ?