Water quality and accelerated winter growth of European catfish using an enclosed recirculating system

Aquaculture of the European catfish Silurus glanis is impeded by the slow rate of growth at ambient water temperatures below 10 degrees C, which are encountered during the winter months in many regions of Europe (such as central France). in an effort to increase water temperatures over this period, fish were held in an enclosed housing where the water quality was maintained using a low-cost treatment plant. For comparison, some fish were held in a separate system that was not enclosed and where water treatment took place in an adjacent earth-lined pond. Both systems were able to maintain good water quality during the winter months but the recirculating system achieved significantly higher water temperatures and rates of fish growth.