The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Aug. 23, 1977
Filed:
May. 01, 1975
Applicant:
Inventors:
Alexander E Birkbeck, Delta, CA;
Craig C Walden, Vancouver, CA;
Assignee:
British Columbia Research Council, Vancouver, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
A01K / ;
U.S. Cl.
CPC ...
119-3 ; 210169 ;
Abstract
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.