British Columbia Research Council

Province of British Columbia

Alexander E Birkbeck

Cecil Craig Walden

Craig C Walden

A fish rearing system. The fish rearing system includes a rearing tank, filtration means and means to recycle water in the system. The system includes an ozone contact unit in which, when the system is in use, a predetermined amount of recycling water can be contacted with ozone in an amount sufficient to lower the total nitrite content of the water to a level acceptable to fish life but not leave free ozone in the water re-entering the rearing tank.

Fish rearing system

A fish rearing system. Water is recycled from a fish rearing tank to a primary filter. Ammoniacal nitrogen load is reduced by rapid removal of nitrogenous solids. The water is formed through a biological filter containing a particulate medium of small particle size. Prior removal of solids prevents filter blockage. The filter is provided with backwash means that include an air scour. The water is reaerated after the filter and returned to the fish rearing tank.

Growing community of inventors

Delta, Canada

Alexander E Birkbeck