As a word of advice: My mentor is nothing BUT a user of rockwool, whether it be the 1.5" cubes or the mini-cubes, so naturally, that's what I use.. The GREATEST thing about rockwool: it's EXTREMELY hard to overwater.. You'd basically have to just leave it in a puddle and/or water it repeatedly throughout the day..
To give you an idea, my plants, once they are sprouted and I see leaves, they get watered everyday.. Rockwool is essentially a form of soil-less medium, so you should treat it similarly as hydro.. The beauty of rockwool is that unlike DWC, watering the rockwool itself aerates it, so you realistically don't need an airstone in a reservoir unless you're insisting on using sweet products like molasses or carbohydrate supplements for your plants.. I have only recently started adding small amounts of this to my res because regardless, you can still get funk brewing in your res ANY time you use something that can be used as food for anaerobic bacteria..
If you want to see how well rockwool works as a complete grow medium, you can check out my grow thread.. I'm not exactly a professional grower and I'd be lying if I said I have it figured out, but I can tell you that it's got the results of DWC, with a similar ease of use as soil.. Sure, you have to pay more attention to pH and EC/ppm, but if you have it dialed in, you literally have to do nothing except some LST, smoke a fatty and just be as patient as possible until your plant becomes mature!! Very over-simplified, but if you want some more info, let me know!!!
