Hi Michael and glad you have the time to promote good soil practices to us. On that topic, how do you feel about adding agricultural zeolite to the top rhizosphere of the soil in a 33% peat, 33% compost/EWC mix, and 33% aeration, and which soil has been amended to Albrecht's standards?
I have heard and read many interesting things about zeolite but have never used it myself. I know it has a high CEC and is used for filtration and detoxification of liquids, which I would assume works by adsorbing toxic heavy metals and molecules onto the - charged sites. My main rule is I don't put anything into the mix that hasn't been lab tested so I know the mineral composition.
For instance, what if you have all of your base cations balanced in the soil/media, but the zeolite turns out to be loaded with potassium? I've seen this with humate ore, incredibly high levels of potassium. I learned this idea the hard way with expanded vermiculite: mixed a large batch of amended peat with vermiculite, sent a sample in for testing, only to find out that magnesium was through the roof, when I had added no magnesium. Turns out vermiculite is almost totally saturated with Mg.
Canadian paramagnetic basalt, OTOH, tests out at 80%Ca, 7.5%Mg, and 7%K saturation, with Fe and Mn in good balance. It's always good to know what one is adding.