9 C.F.R. § 3.157 – Water quality.

(a) The primary enclosure or any other area in which birds may enter must not contain pools or other aquatic areas (e.g., ponds, waterfalls, fountains, and other water features) that are detrimental to the health of the birds contained therein.
1. (1) Particulate animal and food waste, trash, or debris that enters the pool or other aquatic area must be removed as often as necessary to maintain the required water quality and minimize health hazards to the birds.
2. (2) Pools or other aquatic areas with drainage systems must provide adequate drainage and must be located so that all of the water contained in such pools or other aquatic areas may be effectively eliminated when necessary for cleaning the pool or other aquatic area or for other purposes. Pools or other aquatic areas without drainage systems must be aerated and have an incoming flow of fresh water or be managed in a manner that maintains appropriate water quality in accordance with current professionally accepted standards appropriate for the species.
(b) When the water is chemically treated, the chemicals must be added in a manner that does not cause harm, discomfort, or distress to the animals. Should birds appear to be harmed by water quality, appropriate action must be taken immediately.
(c) Pools and other aquatic areas must be salinized for birds that require such water for their good health and well-being in accordance with current professionally accepted standards.