I understand that nutrient availability is shifted around, but the question is why? I've grown in soil, aero, fog, coco, rockwool, oasis, agar, etc. I'll toss a plant in water crystals to see what it will do. Anyone have a smart answer? If you add CR ferts to coco, the pH will be way off in the zone where it is released. Without buffering its going to be what it is. I am surprised that CR ferts work as well as they do with coco.
because the soil typically would lower the ph of your water as it reaches the center mass and then runs off.. so if you have no 'soil' per-say and your using a non-nutritious substitute like rockwool, pellets or perlite then its better to have a slightly lower ph, but usually if you add food to the water it will lower the ph for you to like 6.5, but im experimenting with a perlite only pot right now to see whats the best ph setup.