Recirculation aquaculture systems

Recirculation aquaculture systems (RAS) represent an exciting, eco-friendly and unique way to farm fish. Instead of the traditional method of growing fish outdoors in open ponds, net cages or tanks, this system rears fish at high densities within an operator controllable rearing environment inside a building. Recirculating systems filter and clean the water for recycling back through the fish culture tanks. New water is added to the tanks only to make up for water loss due to splash out and evaporation and to replace that used to flush out fish waste materials to storage tanks. RAS designs have several system process techologies all of which work together to ensure minium loss of water, heat and of course fish stocks, while constantly cleaning and re-using the fish tank water. RAS farms can be designed to various levels levels of complexity, however all true water recirculation designs involve the use of equipment to remove and safely store wastes, clean and re-use water and maintain rearing conditions at or near optimum for the species of fish being raised. In contrast, many older style tank farming systems that have been used to grow fish are termed "open" or "flow through" systems because the water makes only one pass through the tank and then is discarded. Although several improvements can be added to older designs to reduce water usage and create hy-bird types of operations, these are not exactly true water recirculation farms. Benefits of Water Recirculation Aquaculture System Designs Fish grown in any facility must be supplied with the correct conditions necessary to remain healthy and grow. Fish need a continuous supply of clean water at an appropriate temperature and a dissolved oxygen content that is optimum for growth. Water recirculation farms accomplish these tasks. A mechanical and biological system is necessary to purify the water and remove or detoxify harmful waste products and uneaten feed. The fish must be fed a nutritionally complete feed on a daily basis to encourage fast growth and high survival. With that in mind let's review the potential benefits of using Recirculating Aquaculture Systems. Low water Requirements Less Land Requirements Control of Water Temperature Protection From The Elements and Potential Predators Control of Water Quality