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.

DWC Raft construction update

OK, so I had time to make a quick video on the DWC rafts for one of my aquaponics media based growbed systems. I have finished the rafts and will concentrate on the filter system next which will allow me to tie the two types of media together into one system - DWC and Expanded shell grow beds. I will attempt to get the filter system completed within the next several days and hopefully have it completed and tested by the end of next week.

DWC on-going construction.

Hope you enjoy the video, and remember, you can find all of my videos on the Aquaponics Gardener YouTube channel.

http://www.youtube.com/user/Aquaponicsgardener

Until next time, happy gardening.

Construction of the DWC rafts

Well, spring is in the air, and you know what that means....it's time to expand the system and add the Deep Water Culture rafts to the grow beds. So I have purchased most of the materials at my local building supply chains, along with the 12mil B/W Poly Scrim liner material on-line from Americover.com. I based part of my design on the UVI systems, while also making it scalable using off the shelf plumbing parts bought locally.  For the raft side walls, I went with Hardie fiber cement plank 12"W x 12'L. This is very water resistant, and rot/termite proof, so it should be long lasting and it was comparable in price to ACX plywood. ACX plywood would have to be cut into 1ft strips while the Hardie plank is already the correct width. I went with PT 2"x4"x8' for the side rails for durability and weather resistance, with a 1"x 2" furring strip top rails to negate wear on the liner. The assembly process was pretty straightforward and I was able to complete construction of each raft, less the liner installation, in a couple of hours. I measured off an area that was 25ft x 25ft and placed woven weed block down prior to raft construction. I laid this in a cross hatch pattern, double layer which was approximately 1100 sq ft of material and attached it with ground pins. I will be adding edging material later and filling in the area with expanded shale or gravel.

Here are a few pics of the raft construction process, note that I used all galvanized fasteners for construction.

 1"x2"x24" PT stakes were added as side support and to negate any shifting, these were attached with 1/4"x3-1/2" galv. carriage bolts w/nuts and washers.

Since I have two aquaponics systems, I am building two rafts per system for a total of 4 rafts. Each raft is 4'W(actual is 51")x16'L, this provides me with 256sq ft of growing space, with a an average of 30 plants per 1sq meter (10sqft), I should be able to have approx. 768 plants along with those in the grow beds. I also intend to add additional  4'x4' DWC rafts inside the greenhouse. This should up the count to approx. 1000 plants between both system. Of course, once the rafts were finished I had to paint them to match the greenhouse and our home.

Based on my previous design, I am using 2" PVC to connect the beds on the far end using 2" DWV 90deg EL's and 2" non caulking floor drains. The floor drains have an internal rubber busing which can be tightened down on the 2" PVC pipe and if necessary loosened later for removal or expansion.

The floor drains require a 3-1/4 hole saw which is a perfect fit. The only problem I ran into was that the concrete board pretty much destroyed the hole saw after 4 holes...so I will have to buy another one when constructing the second set of rafts..which are kind of pricey at $17 a pop, but hey, it for a good cause, so enough about that. In the pics above I used a scrap piece of board to test the size and fit of the drain...can you say perfect.

Now on to drilling the holes in the raft beds.

 These holes were placed at 5" from the bottom and 25-1/2" on center of the Hardie plank. Remember, I build the rafts 51" wide.

And with that, I end this post as it has now been raining for several days, and I will need to continue this after I have progressed further on my installation of the DWC rafts, hope you find this helpful.

Time to plant for seedlings

OK...so I'm a little late on planting my seedlings due to other domestic obligations ...anyway, I have picked up some seedling trays from Amazon that are being used to start my seedlings. I tried using white grow cubes on my bell peppers in the past, which sprouted fine, but did not allow for enough oxygen to the roots and too much water causing rot. This time around I'm using peat moss. I have to pack each seed cell in the tray with peat moss, which should provide a good foundation for the roots. I am using a combination of rain water and FT water to sprout the seeds.  Hopefully, the greenhouse will provide enough light for stronger growing plants. I am growing two varieties of cucumbers, three different types of tomatoes, some heirloom, along with kale, lettuce, squash, etc. etc. etc. Once the sprouts are large enough, tomatoes will be placed in the media grow beds, along with the cucumbers while most of the rest will go into the DWC rafts once completed.

Insulation for the Fish Tanks

Sorry everyone for not posting lately, too many projects going on and with the daily grind of  "normal life" I haven't had much time to pursue my Aquaponics dream. Anyway, I decided to insulate the tops and bottoms of the fish tanks with 1" extruded polystyrene foam board that I picked up from Home Depot. I purchased four 4' x 8' sheets along with a couple of cans of 3M Super 77 spray adhesive to glue all the foam board up with. It was a challenge since I had to piece everything together on the top of the tanks due to the fact that I couldn't move the grow beds. Each individual piece had to be measured and cut to fit as no two pieces were the same. Time to complete 2-1/2 days. It was worth it and has cut down on the evaporative water loss from the fish tanks, which in turn has cut down on the humidity in the greenhouse. Oh..and did I mention the cost saving on electric to heat the water.  It dropped my bill by about 30%, almost to it's typical winter norm. And the cost for all of this was about $60 dollars. This is one of those " I wish I had done this sooner or first" situations. Hey, it's a learning experience...right? Oh well, I will know better in the future.  Of course, I am a little late on planting for seedlings, but that's for the next post. Until next time....

Solar Hot Water Heater for Fish Tanks

OK...so I got the great idea of building a solar hot water heater out of black poly tubing and having that connected to one of my fish tanks in order to cut the electric bill down on the aquarium heaters I run. I am having mixed results, with a net gain of 4-5 degrees over the ambient temperature of the fish tank water. I was expecting much more.

Initially, I placed 75ft of poly tubing into a 4'x4' box (2x4's) made out of Dow blue board and clear / white poly carbonate panels with the inside painted black as shown in the video.  This is all connected to an Aquatop 496 GPH submersible pump which has been choked down to about 250 GPH to give the water enough transit time through the pipe to heat up. I found that I did not have enough pipe so I added another 100' to the existing pipe, I am in the process of sealing the box, and I will need to use glass on the front to better trap the heat as the poly panels don't do a good job. I have a resource to buy cheap used windows and will be heading down to look for one soon.  I have posted some pics of the unit as well.

 Until next time....

The sewing of Romaine Lettuce and Collard Greens

Aquaponics is amazing....after sowing several dozen Romaine lettuce seeds of various varieties. I was surprised to find that after 3 days most of the seeds had sprouted. This is truly amazing considering that normal germination for these seeds type is 7-10 days. I also did the same with a pack of Collard Green seeds and unexpectedly these also sprouted in 3 days while normal germination is 10-21 days. I have included a few photos to show the new babies.

 You can see the new lettuce sprouts next to the new Bell Pepper plants in the pic above.

 A closer view, I'm going to have to cull a few of these as they get bigger.

And yet more....

Here is a shot of the collard sprouts.

I also had a Basil harvest this past weekend due to the fact that the plants were starting to get lengthy and falling over. I cut these back and dried the leaves. I still have quite a few younger plants for fresh cut leaves when needed.

Next post  to follow will provide an overview the new solar hot water panel I put together to heat the fish tank water.