i was just browsing and came accross this and figured id throw in my two cents worth. i dont see how giving the rock a bath whether it be vinegar or acid is going to draw nutrients from it. i can see how it would clean off the outer surface but as far as absorbing the nutrients out of the rock, someone will have to explain that one. the concept of cooking to allow the
bacteria to eat the nutrients is sensible. i think this will continue to be a debated topic because i dont beleive any of us have the capability to measure the nutrient content of the rock. but i can be wrong. but it deffinitely sparked my interest an will be on the top of my list of things to research.