This week saw us continue with the central drain in the vegetable tunnel at the new commercial site. All water is going to end up in this drain and it will be filled with gravel to provide even more bio-filtration and who knows? Maybe we can even grow something in this damp environment. Watercress? Rice?
Just to recap, the water flowing from the Tilapia ponds will go through a solids filter, then into the drain and then into the sump. Water to the growbeds will flow into this drain and the strawberry towers will also drip directly into the drain. So here is how we are going about building it.
First we dug the channel and then lay plastic down.
Then we concrete it. We mixed an admix called Sikalite into the cement to provide even more water-proofing. Levels are important. It has to be completely square across but have a gentle slope down to the sump.
Then we built a small brick wall all the way down the length of the drain right down to the sump. It is one brick high at the top of the tunnel becoming three bricks high at the sump side. I am going to make a fibreglass rim flow over the end and into the sump. This is what it looks like at the end.
I have also mocked up my solids filter and it will consist of three compartments, namely filtration cloth and charcoal, secondly coral and oyster shell, and thirdly a settling section in which I’ll probably stock some Tilapia fingerlings to eat any remaining solids. Here is roughly what it will look like.
Meanwhile at our completed site the plant growth is quite phenomenal. We are being visited next week by some members of the local Town Council and I am sure that they will be highly impressed at what Aquaponics can do towards food security. Just look at the difference after only a few days.
Believe it or not, those giant leaves in the foreground are beans !!
Enjoy your weekend