The bacteria appeared to be doing their thing – changing ammonium into nitrite and then the next type changing it into nitrate – thus, the system was prime for the introduction of the fish. They arrived on May 29th and seemed miniscule at 1 to 1.5″. They have lots of growing to do before they are “plate size”. Plus, they are going to need to be a bit more substantial to provide adequate fertilizer for my plants!
Cooler filled with tilapia fingerlings.
The pump and associated plumbing had just been installed with help from my friend, Ken – who’s worth multiple times his compensation of minimum wage plus food.
Excitement mounted while we awaited the first syphon event to recylce the water. We took ring-side seats for our lunch.
The first bed that was functional was the raft bed. Plants float on/in styrofoam sheets with their roots dangling in the nutrient-rich water.
The plants in this bed will be produced in waves. Here a space holder is over the right side to reduce evaporation and heat loss. Tilapia like it warm.
The plants for this bed had been germinated in the basement in rock-wool blocks with bottom heat and lights.
A close up of the germlings in rock wool with a dab of media to cover.
I devised floating sheets with 2 spacings, depending on anticipated ultimate size. I then drew a grid on the styrofoam and cut openings with a holesaw. Little plastic baskets fit with their rims resting on the edge of the hole and the individual rock wool blocks are inserted in the baskets.
Baskets set into holes.
Sprouted plants in rock wool blocks.
The media bed is a bit more complicated. The local peagravel turned out to be much too alkaline so I needed to resort to a pricier fix – a product called Hydroton manufactured specifically for aquaponics. It weighs about half the comparable volume of peagravel, but also needed to be rinsed prior to filling the bed.
Sixteen bags of this stuff is a lot of weight!
The media bed is 11.5 inches deep with the Hydroton, but the syphon triggers when the water is 10″ deep so the top stays dry and doesn’t harbor algea. Here is the first crop in the media bed – strawberries, tomatoes, peppers, eggplants, and herbs. Stuff that likes it warm, plus strawberries ‘cuz they taste so good! We’ll see what does well under these conditions. Stay tuned for updates!
***The aquaponic system was decommissioned when I transitioned to a full-time off-farm job. The CSA required too much work and the system was oversized for a single consumer.
Newly planted media bed.