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SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament SpeciesScientists Discover Mysterious New Fish in the Red Sea – and Have Never Seen It Again OceanEye to eye with Britain's hidden sharks at SharkAdemy - Oceanographic RiversIn October, biologists surveying a New York harbor for invasive fish pulled up a bright yellow one. It wasn't an invasive species at all OceanShedd Aquarium Sends Shark Eggs to Bolster Wild Populations SpeciesA rare fish has been found in Lake Ontario, North America, whose entire body is golden. It is a nati..OceanThe Great Sea Reef Is Fiji’s Wildest Dive, and a New Frontier for Conservation OceanEckerd College professor contributes to designating Biscayne Bay an Important Shark and Ray Area SpeciesRio Verde Grande Survey Identifies Fifty-Three Fish Species Facing Flow Reductions FisheriesAdams River Salmon Run in Thompson-Nicola IndiaHilsa production dropped 26% in five years, fisheries minister tells parliament

EveryFish

Recirculating aquaculture system

A closed tank farm that cleans and reuses its water, letting fish be raised indoors with little water and space.

Also: RAS, biofloc

In a recirculating aquaculture system, water flows from fish tanks through filters that remove solid waste, then through a biological filter where bacteria turn toxic ammonia into less harmful nitrate, and back to the tanks, with oxygen added on the way. Up to about 99 per cent of the water is reused each day. These farms can be built anywhere, even in cities, and hold fish at high densities, but they use a lot of power and need skilled care. Biofloc, popular with small farmers in India, uses clumps of bacteria in the tank to clean the water.

See also

Nitrogen cycle (aquarium)Aquaculture Mariculture

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