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Table Top Recirculating System

Click here for a diagram of the recirculating system

A recirculating aquaculture system‚one that recycles the water it uses‚is the most environmentally friendly method of aquaculture. A recirculating system also makes sense when water of good quality is limited, or when discharged water needs to be kept to a minimum.

Water Flow of a Table Top Recirculating System
The recycling of the water begins when water drains from the culture tank with the fish and into the particle filtration chamber. This filtration chamber contains a particle filter bag, which filters out the excess feed and waste of the fish.

The water travels down through the particle filter bag and out through a pipe that is connected to the pump of the recirculating system. The pump drives the water through the system. It is always located after the particle filtration chamber so that the recycled water is free of particles that may clog the pump.

The water is then pumped up through a pipe that branches off perpendicularly at its midpoint, creating a bi-directional flow: one water path continues to flow up and the other path flows through an ultraviolet filter system that minimizes the amount of bacteria or viruses in the water.

The non-UV treated water flows up, across and down into a biofilter tank containing biomedia (plastic material with large amounts of surface area that helps remove ammonia and nitrite created from excess feed and waste). The biofilter tank also contains an airline with an air stone that helps maintain the system's dissolved oxygen level and the agitation of the biomedia.

The treated water from this biofilter system flows out and up to an intersection point where it meets with the UV-treated water. The treated water from both systems flows out together through a spray bar into the culture tank, offering the developing fish a clean and healthy environment.

Related links:

All About Aquaculture
Fish Life Cycle

Species raised at the Finfish Hatchery
Facilities overview