From Hydroponics to Aquaponics and Back Again
Last week, I shared my experience of a visit to The Green Exchange, where I learned how to grow salad using chemical-free hydroponics, which made use of ethically sourced soil and biochar. For this week’s venture I returned to Incredible Edibles in Todmorden to meet Jed, a grower at the Incredible Aqua Garden.
My partner has been excited about aquaponics since our permaculture course, so I decided to take advantage of an invite to learn what is entailed, and wondered if I’d return home as similarly enthusiastic.
Aquaponics is a system of growing food without soil by creating a symbiotic relationship between fish and plants. It combines aquaculture with hydroponics.
Fish are kept in tanks and their excrement produces ammonia, which is toxic to the fish. Pumps draw the excrement into hydroponic beds. Bacteria convert ammonia into nitrites, which in turn, fertilise plants. This has the effect of filtering the water which is then pumped back into the fish tanks.
Two sources of food in one!
The Incredible Aqua Garden
We first checked the health of the fish by checking the health of the water. We fed the tilapia, goldfish and fry. Detailed data is kept on the records that are taken with each inspection. The design of the system and its software are freely available. The system has been put together to show that it would be possible to make use of recycled materials in the construction of something similar.
Like the Green Exchange, it was immediately apparent that the Incredible Aqua Garden is relatively well-funded, with purpose-built growing rooms, kitchen, and space for educational work. Additionally, food is grown using hydroponics and also in external and internal raised soil beds and a polytunnel.
Soil, no soil, to dig or not to dig?
Jed has been an apprentice with the project for the last year and soon to leave. He’s passionate about no-dig and chemical-free gardening and shared his thoughts on how not every aspect of the Incredible Aquagarden suited his preferred way of working. He was clearly happier with his no-dig beds, polycultures and being outdoors. He illustrated the difference in the quality of plants depending on the different growing methods used through a tasting of different lettuce leaves. It was an experience that said more than any words could.
Outdoor grown lettuce was stronger and more flavoursome than the vertically grown lettuce. The difference was striking. Additionally, mushrooms were not only growing in the outdoor beds, but also the soil beds indoors – a sign of a healthy subterranean ecosystem. Jed pulled back some of the soil to show the web of mycelium that had formed just below the surface, a network that would be quickly destroyed by exposure to UV rays if the soil was opened by digging. He didn’t need to convert the converted, but I enjoyed the pride in his demonstration of what he’d created.
We watered the indoor beds and planted mixed mustards in the polytunnel. I left feeling I’d not done a great deal of work today, but was reminded of how permaculture reduces the workload most farmers complain of!
Jed shared the name of an organic farmer who advocates the no-dig method. I thought I’d pass on the inspiration.
Charles Dowding shares his 35 years of experience, including seasonal tips and a forum here.
For me, I was fully in agreement with Jed, it was soil beds over aquaponics and no-dig over dig. But, I could be persuaded by the idea of keeping fish.