System Technology
3.2 Disposal of Waste
Recovery and digestion of fish effluent is more important in aquaponics than waste disposal. A large portion of feed is excreted as solid waste. Nutrients essential for plant growth are trapped within this concentrated slurry and should be recovered to reduce production costs and limit the need for nutrient supplementation. Recovery of these nutrients moves aquaponic production towards a zero-discharge system. Nutrients can be recovered through aerobic or anaerobic digestion of solids.
· Kentucky State University3.1 Water Sources
Sourcing water is an important consideration, as it directly impacts system management and performance. Typically, 1-3% of total system water is replaced per day depending on climate, time of year, and crops being produced (Somerville et al. 2014). Water is lost in the system through evaporation, transpiration into the plant, and through normal processes of splashing, cleaning, and harvesting. Water with a salinity above 0.8 parts per thousand (ppt) are typically not suitable for aquaponic production as the majority of cultured plants do not tolerate even a small degree of salt (Shannon and Grieve 1998).
· Kentucky State University