DWC Raft Construction Update #2

OK...so I have finished hooking all the components up for the new DWC rafts in system 2. All is working according to plan. The only adjustment I had to make was to the riser tube coming off the bottom of the FT's. I had to shorten it by 1" as I was having an overflow problem in one of the FT as the ebb/flow grow bed were draining. Easy fix, with a hacksaw and 2" coupling. I have also built a weather protective box for the pumps and air blower. I still need to paint it to match the greenhouse...shouldn't take more than a couple of hours to paint.

I have included a video overview of the system so far....

  I purchased 4  - 4' x 8' extruded polystyrene 1" foam sheets from Home Depot for use as my rafts. I then cut these into 4' sections and drilled 3" holes, using a hole saw, in each to accommodate 3" net cups.

 I have 5 rafts that each have 36 holes on 8" centers and I have 3 rafts that have 16 holes on 12" centers. This gives me a total of  228 holes for plants in both rafts combined.  The 8" center hole rafts will be used for leafy vegetables such as lettuce, Kale, Greens, and Herbs, while the 12" center rafts will house tomatoes, cucumbers, squash, peppers, cauliflower, and broccoli.   I had to paint the tops with a latex based paint to provide some protection from the UV rays of the sun.

All painted up and installed in the rafts.

I also drilled 1" holes about every 2' for air stones coming off the 1" PVC airline running down the middle of the rafts. As you can see from the photo, there are plenty of bubbles coming up against the rafts.

After completing all of this work, I noticed that the top layer of weed block was breaking fairly rapidly in the sun, so I decided to lay down UV resistant tarps over the weed block, hopefully I will get a couple of years use out the tarps before they need to be replaced.

 Ultimately, I will be placing pea gravel down over the weed block, but no time for that now...I'm off to get some Mozambique Tilapia at Overton Fish Farms....

Next up ....the Tilapia.