There is no real way to do hydro without spending the $30 and buy a PH meter. You will also need PH up or down, and 2 different callibration fluids, probably 4 and 7. I keep my PH at 5.2, and calibrate once a year or so. I have done a lot of research about the correct PH.

This sounds worse than it is once you do it a couple of times. It takes me about 10 minutes now from start to finish to mix up a batch and feed my plants.

I got all my stuff at a hydro store, but you can find it much cheaper on line.

I don't worry about mixing a bunch of things for different stages. I use fox farm grow big and a couple drops of superthrive for veg, and fox farm big bloom only for flower. I have great results and I just follow the directions on the bottle (2 teasp. per gal.)

Don't mess with organic crap. Just pump em full of chemicals - they love it. If you are worried about smoking chemicals, you can always feed with water only the last week or two.