I tried dwc a few years back and it was a failure lol. So sorry not much help! I run a ebb and flow setup which is great for me. If i have a power failure the plants will last quite some time (24+ hours) and that is a concern here. I have two totes, 100L on bottom and 45 on top. 4-6 net pots suspended in upper tote with hydroton balls. I run pump 24/7 and have no air pump just floom. As with all hydro that uses a res (dwc included) it is IMO crucial to keep water temps around the 68-70 range for the most part. Also I never go above 700ppm's tds. If you are interested I can send you pics of my setup, its a DIY thing and total cost was $125 for everything for each unit. The nutes i use are from Ez-Grow, it is a company that sells to name brand companies. Its cheap and good! $50 for two one gallon jugs of A and B. Again keep in mind I just started so I know shit lol.