The principles behind aquaponic exchange rates, in dual loop systems are driven by the need to exchange water from the recirculating aquaculture system. This water exchange is a water quality requirement for the safe and healthy production of the fish species cultured.
There is confusion around how dual loop aquaponic systems work in terms of balancing the water needs for both the fish and the hydroponic systems. The water exchange rate for aquaculture are well known and a relatively simple formula 1. Water requirements of hydroponics is also known 2, well researched.
The formula for working out the overall water mass balance out can be complex due to the various rates of nutrient uptake of so many cultivars and the sunlight and environmental controls that manipulate the hydroponic system. In this article we will discuss the first part of the equation, the aquaculture.
References and Further Reading:
- Losordo, T., & Hobbs, A. (September 2000). Using computer spreadsheets for water flow and biofilter sizing in recirculating aquaculture production systems. Aquacultural Engineering, Volume 23, Issues 1–3, 95-102. ↩
- Pardossi, A., Malorgio, F., Incrocci, L., Carmassi, G., Maggini, R., Massa, D., & Tognoni, F. (N.d.). Simplified Models for the Water Relations of Soilless Cultures. Pisa, Italy: Dipartimento di Biologia delle Piante Agrarie, University of Pisa. ↩