28 Pa. Code § 18.23 – Recirculation and filtration.

(a) A pool shall be provided with a recirculation and filtration system, except when there is a flow of water of the quality and quantity through the pool which at all times conforms to § § 18.22—18.29.
(b) When sand or anthrafilt filters are used, equipment shall be provided capable of continuously adding with reasonable accurate dosage, coagulant ahead of the filters.

The provisions of this § 18.23 adopted September 18, 1971, effective September 18, 1971, 1 Pa.B. 1921.