When human beings first settled down to agriculture and changed their method of securing food from hunter gatherers to farmers, water was one constant need. As early as 6000 years ago, humans such as the Sumerians devised vast and intricate systems to irrigate their land and provide the much needed water for their crops in dry lands. From the plains of Mesopotamia and the canals of the Nile Valley to a warehouse in east London, irrigation has underpinned the world’s great civilizations.
Our irrigation system uses over 200m of piping to pump nutrient rich water from the fish tanks in the aquaculture area to the newly installed grow beds in the hydroponics area.
We use a flood and drain system, which means that the benches are flooded periodically instead of being constantly flushed with water. This is automated and regulated according to each plant’s optimum nutrient uptake.
As the plants take the nitrates out of the water they clean it, ready to be pumped back into the fish tanks.
The aquaculture area consists of twelve 3000L fish tanks, each containing around 150 fish. That’s over 4,000kg of fish per year! These fish are our natural source of fertiliser for our plants, but they will be harvested periodically too.
The aquaponic system we are using at the farm is technically the same as at the Box, but on a much larger scale!
This makes it advantageous for us to have the water ph testing, fish feeding and bench flooding all fully automated. These will be controlled by a Priva Building Management System which will monitor the nutrients, salts and impurities in our water. Because of plant transpiration, it will also be necessary to add about 5% fresh water to the fish tanks to keep them topped up.
This almost closed-loop circular system demonstrates how far we have come, and can go in the future, with the precious use of water in agricultural production.