System built 2015.
Due to the nature of recirculatory aquaponics, this system can worked for years without the need for any water changes or filters. The fish wastewater, rich in ammonia, is converted by bacteria into nitrates, which are filtered from the water by the plants. Clean, nutrient-free water is then returned to the fish, while the plants collect the organics to be used for energy and biomass.
One of RCG's original student projects, this small, 500 gallon recirculatory system was designed to prove the viability of aquaponics in sub-optimal environments. Due to the nature of where Roger's Community Garden is, surrounded by large Eucalyptus trees and close to the ocean, the previous team decided to build this as a test bed to make sure that the fish and plants could survive. Furthermore, due to the wide temperature swings the region can experience, the team wasn't sure if production fish could be used, and settled on Koi.
The original project team has since graduated and the system had been in maintenance mode for several years since, but as of 2021, a small team of RCG members has been working to bring it back. Through months of hard work sifting gravel, filtering water, patching holes, and cultivating bacteria, the team was able to restart the system from the ground up.
In 2023, the project leads have been mitigating issues with the siphon that results in the bed not flooding with enough water. The aquaponics system is slowly returning to a steady state with resident bluegill fish and herbs.
The system is separated into three sections: tank, upper flood bed, and lower flood bed.
Our aquaponics tank has bluegills, though systems can also use tilapia and koi.
Kale growing in lower aquaponics flood bed.