A goal for 2014 is to install a small aquaponic system in the greenhouse. Aquaponics is attractive for many reasons. It is a way to have locally sourced (and totally organic!) fish, but also the fish waste is cycled through a vegetable production system cleaning it for the fish and providing nutrients for the plants. Vegetable gardening this way requires almost no weeding, can be done year-round, doesn’t require application of synthetic fertilizers, is automated so watering is optimal and not an added chore – and the work is done, mostly, at waist level!
Challenges have been to have adequate buffering (CaCO3, a.k.a hardness) in the water and yet have a pH that is acceptable. The key to this “ecosystem” is developing a bacteria culture in the water and on the surfaces in the system that changes the ammonia from the fish into nitrites then nitrates that the plants can remove and use. Water pH, temperature and hardness levels are all critical for bacteria growth.