The recirculation and purification system shall be operated and maintained so as to keep the pool water clean and clear. Under no circumstances shall the pool be used when a black disc, six inches in diameter, on a white field, when placed at the bottom of the pool at the deepest point is not clearly visible from the sidewalks of the pool at all distances up to ten yards from such discs. Such a pool shall be closed and shall not be reopened until the water is clean and clear, and upon specific approval of the Health Officer. (Ord. 3440 § 1 (part); June 24, 1975.)