Abstract: A swimming pool chlorinator that utilizes a cylindrical housing that has an internal chamber. Within the internal chamber is concentrically mounted in a close fitting manner a valve member. The sidewall of the housing has a series of elongated slits and also the valve member has a series of similar elongated slits. The housing has mounted thereon at least one suction cup with the suction cup to be securable to a swimming pool wall surface or other surfaces associated with a swimming pool and beneath the surface of the water in the pool. Within the internal chamber of the housing is located one or more chlorine tablets. The valve member is to be adjusted relative to the housing so that the slits of the housing are unrestricted permitting free flow of water through the housing or the slits are restricted partially thereby limiting the amount of flow of water through the internal chamber.