I do DWC, but like to keep it simple. I mostly use individual 5 gal buckets or smaller individual totes. This enables me to do a perpetual harvest and also grow different strains with differing characteristics at the same time. When you are in one tote or your totes are fed by a single reservoir all the plants need to be the same size and have the same nutrient requirements. And I want to check my plants out on a regular basis and like to be able to move them around and also remove them from the closet for inspections and to clean the res. I personally find it easier and more to my style to have individual buckets. It is more work, but the way I grow, an individual res just isn't feasible. You are going to find what works best for you and how you want to grow.
The building of the buckets is pretty simple--a hole in your container for the net pot and a couple of small holes for air line/stones. Each bucket needs to be aerated--this is what keep the roots from drowning. I use a small commercial 6 outlet most of the time and run 2 air stones to every bucket or tote. I also have a couple of smaller/quieter pumps that are dual outlet and I use for an individual bucket.
With hydro, you are going to need a decent pH meter, as correct pH is critical for hydro. You will also need calibration fluids and pH up and down. You will also need something to measure the ppm of dissolved solids in your solution. This tells you how strong the solution is. We start with a very mild solution when we first start feeding the plants and slowly work up.
There are tons of tutorials on making DWC units. You might want to check out some You Tube videos on a simple set-up.
