Abstract: An animal waterer drinking well apparatus is utilized with an animal waterer having a cover with one or more circular openings formed therein. The apparatus comprises a circular drinking well having an outwardly extending lip at the upper end thereof and which is adaptable to be inserted into one of the openings. A plurality of slots are formed in arcuately spaced relation in the circular wall of the well slightly below the lip, and a flexible ring having arcuately spaced projections, is inserted into the slots. The projections combine with the lip to embrace circumferential portions of the cover about the opening and secure the well to the cover. An annular, inwardly extended collar is formed integral with the well and is spaced below the arcuately spaced slots; and a circular float having a diameter slightly less than the inner diameter of the well is adapted to seat upwardly against the collar due to water pressure within the well below the float to form a seal.