First of all remove the idea of "eating" from the way you think of nutrients - they ARE NOT FOOD. They make up the elemental needs of plants stricktly in the most base sence of chemical reactions, similar to the way people use multi vitamins.
Of those vitamins we are giving plants, 96% are provided by the atmosphere (C, H, and O). they cannot be given to plants, however we can impede the plants access to them - (which is usually the cause of nutritional imbalances. ) So N,P,K,Ca,Mg,S,Mn, etc all together make up 4% of the elemental needs of plants. (light is the plants food.)
Next, the idea that they can "drink" and not "eat" ceases to make sense. Plants do have selectable membrane at the epidermis of the rhizosphere, however the depth of the ability for them to select is probably minimal, and for our purposes serve mostly as a "clotting" agent whereby the root becomes less active or even inactive and begins to rot. This is why UC roots is so effective, it exfoliates clotted roots.
Finally, the mantra pH up, ec down = good and pH down Ec up = bad, is all well and good if your flooding and draining, but for our purposes leaves much information to be desired.
Let water consumption be your guide, plants that are not up-taking water cannot be up-taking nutrients; where-as plants using 2 gallons per day, per plant site, of very very low solution strengths can be up-taking astronomical total nutrient values.
