Water Management Applied in Recirculating Aquaculture Systems.

Abstract

The authors present results and an improved wastewater technology applied in recirculated aquaculture systems. Due to the high value of the investment, the total number of the recirculated aquaculture systems is small compared to the classical (cages, flow-through, ponds etc.) aquaculture. The high investment cost is given by the existence of the wastewater treatment stage. That is why, new cost-effective technologies for wastewater treatment are developed. The authors propose an improved mobile bed biofilm reactor to be used within recirculated aquaculture systems. The nitrogen compounds (ammonia - the main contaminant produced by the fish metabolism, nitrates and nitrites) are thought to be the main pollutants generated by the recirculating aquaculture systems. The improved technology was tested in laboratory conditions and the obtained results confirm the improvement of the treatment efficiency. A new (material and shape) biofilm carrier, used in mobile bed biofilm reactors, is described by the authors. The new material has led to an increased quantity of the attached microorganisms by more than 250% compared to the plastic materials (high density polyethylene) commonly used for the biofilm carrier manufacture. Synthetic wastewater was used during the experiments.

Keywords

• wastewater treatment
• recirculated aquaculture systems
• mobile bed biofilm reactor
• polyethylene
• Romania