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Fanatic Aquaponic Grow Bed Build – Bed #1 Complete!

Now that the tank is finally in the ground, I can now move on to the grow bed building portion of the greenhouse.

As before I’m sticking with the reclaimed lumber I had from the shed tear-down. Expenses here included screws, pond liner, paint and a few drill bits (go through them like butter).

As with everything in this build, I’m making it up as I go along.. i.e. I have no set plans to work from, I’m just building as I go based on a rough sketch I did when this whole ball of wax got started 😉

Originally I had planned on making the bed size 8Lx4Wx1H, but revised that just a bit to 8Lx3Wx1H. This reasoning came when I decided to take a look at how much space such a grow bed would take within the greenhouse itself. At four feet in width, it became apparent that my reach across the entire width of the grow bed would become difficult as I would only have access to the bed from 3 sides versus 4 (since that side will butt up against the outer wall of the hoop house). This was confirmed when during mock-up the wife mentioned as much for herself.

So, now the final tally will be 24 sq ft per grow bed versus 32. I’ve also decided to go solely with grow beds versus a split between beds and an NFT raft setup. Mosquitoes are a big problem and I’d just as soon avoid that fiasco all together.

Next up will be painting the growbed to help it stand up to the elements and so that it looks a bit better aesthetically. I’ve got several more of these to build, but now that I’ve been able to get through the first, I now know what I need to put together from a parts list standpoint and can pre-cut everything before hand going forward to save time.

Once I’ve got the first beds painting completed I’ll then start working on initially placing them in the hoop house and getting it leveled, lined and plumbed (this is another little bit of build I’m looking forward to with the PVC.. as I’ve never done it before, it should make it very interesting) 😉

Some items of note that came up after a good discussion with a fellow AP’er.. the ratio of fish to grow bed capacity came up. Now what’s considered a safe ratio is 1:1, that being 1 fish to 1 square foot of grow bed. He noted that he originally started off with 50 fingerlings and would eventually have two grow beds totaling about 48 sq ft of growing space. Problem was he never got to building the second bed due to family constraints. Of the 50 he started off with he’s now down to about 30 due to not properly screening off his pump. 20 or so poor little fish got sucked up into his grow bed and that was that.

Even so, at 30 fish he is now noticing his ammonia levels getting high. After screening for anymore dead fish, reducing the amount of feed given to the fish and his ammonia still on the high side.. the deduction is that there is just not enough biofiltration going on with the one grow bed to take care of all 30 fish (which within the span of 6 weeks went from 1 inch to nearly 5 inches!.. bigger fish = more poo = more ammonia). He is now working on plans for a second bed.

With that in mind I’m going to start with even more of a buffer and limit it to about 20 fish per grow bed.. or about 1:1.2 = 1 fish to about 1.2 sq ft of grow bed (roughly 160 fish at maximum capacity). Ultimately the main plan is to keep the system as stable as possible. I’d rather er on the side of caution then have to restart a new cycle on a system. Anyway, that’s my 2 cents.

More updates to come!

Urban Farm Fanatic Item #2 – Aquaponics Greenhouse… The Build Continues!

Well, the opportunity to finally get down to the fun part of building the greenhouse, i.e… actually building the greenhouse has come! No bushes to dig out, no irrigation to dig around for, no screening out river rocks. Just fun old, “Break out the power tools and grunt like Tim the Toolman Taylor building!!!” Arrrrghhh arrrgh aaahhhh!!! 🙂

Originally my thought was to just start adding in a few images as the build progressed, but by the end of the day I had realized that I had been quite the camera bug.. and so putting together just a few still frames wasn’t going to do this build the justice it deserved. After all, you plan a project for months, you need to give it the full blogging treatment. So, I decided to dust off what little knowledge I have about video editing and put together a nice little clip of the days progress… and yes, this all occurred in just one day! (The magic of the hoop house build.) All together about 8 hours of work.

After completing the first days work, I’d have to say the hardest part of the initial build was the 2x4x6 foundation. I was wanting that to be as level as I could get it, but realized that the ground was in no way level for my needs. I pre-drilled holes for each of the pieces on my back porch which I knew to be level, then moved them into the yard for assembly (the greenhouse’s dimensions are 12×40). I used scrap blocks to add support to the low lying areas. Followed that up with the sledgehammering of the 3 foot re-bar pieces (drove those half way into the ground.. my right hand is dead by the way from swinging an 8 pound sledgehammer).

As for the easiest part, that would be the assembling and installation of the PVC supports. Got a nice little 45 degree joint to mount the two 10 foot sections together, slid one end over the re-bar on one side, then bent and slid it over on the opposing side. That part took all of 20 minutes to complete the entire hoop!

Next weekend I will be receiving a large order of rock that will be applied to the foundation. The plan was to do that anyway and I thought it better to work with the rock in order to achieve a level base rather than trying to dig up the surrounding dirt and raking that around. But as I said.. next weekend.. right now the old bod is ridiculously sore, so I’m going to be giving it a breather before I put it back to work!

Enjoy the video!!! 🙂