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:
Mar. 26, 1996
Filed:
Dec. 13, 1994
Applicant:
Inventor:
Robert I Wiedemann, Shepperton, GB;
Assignee:
Pet Mate Limited, Surrey, GB;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C02F / ; A01K / ;
U.S. Cl.
CPC ...
210 86 ; 210 95 ; 210109 ; 210151 ; 210169 ; 210202 ; 210203 ; 2104162 ;
Abstract
A filtration unit for an aquarium tank comprises a biological filter chamber which is cyclically exposed to air and water without the use of conventional syphon means. Alongside the chamber is a U-tube arrangement one branch of which communicates at its upper end with the upper region of the chamber. Compressed air is continuously admitted to the chamber, e.g. by bubbling up beneath its open bottom end. When the water in chamber drops to the level of the bend of the U-tube air in the chamber expells remaining water from the U-tube and is able to evacuate chamber, enabling it to refill with water.