I made my own rdwc,and learned a few things along the way,I wanted my set up to feed the first bucket then that bucket would flow into the next and so on.I only have 4 buckets and an 18 gal tote as my res. I first tryed to do it with all 1/2'' tubeing but it didnt move enough water for my likeing,so now I have 1/2'' going in to my first bucket with a 1/2'' line plus a 3/4'' line going out to the rest of the buckets and back to my res. I have a 400 gph pump that is to much so I have a ball valve on the in line to the first bucket to control the flow, and it makes res. changes a breeze compared to my old single buckets. the water is moveing from bucket to bucket fairly fast.this is my first grow with this set up and I am just vegging some plants now that should be ready to go into the flower room in a week or two,then I will see how my set up works,I also have 2 -6 inch air stones in each bucket with plenty of air to supply them.and I also have the buckets wrapped in 2 inch silver backed insulation and a custom made cooler that holds my res. I will post my progress