Aquaponics re-circulates and filters fish effluent through cinder where it is biologically degraded and converted to plant available forms of nitrogen. Plants then uptake the nitrogen derived from fish waste, to produce vegetables for consumption while maintaining water quality necessary for healthy fish growth. 

When asked why they chose to start and continue aquaponics at home, community members often cite “fish and poi,” a reference to staple foods that are frequently grown in the systems, reminiscent of traditional food production systems of taro (poi is made from the corm/root of taro) linked to fish ponds. Unfortunately, one of the challenges that have been identified in aquaponics systems is that the taro corm often does not form quickly or particularly well. We hypothesize that the primary reason for this is high nitrogen concentrations in the fish effluent  promoting foliage growth at the expense of corm growth. To test this hypothesis, our team has designed a dual-tank system that allows for fish effluent to be excluded from half of the kalo at mid-maturity. These plants will instead be provided with fresh, low-nitrogen water for the second stage of growth to determine if this increases corm growth. Water quality is being evaluated weekly and periodic comprehensive tests of water and tissue nutrient concentrations will conducted to track differences between treatments.