Abstract: Tubular lamp wells used to protect ultraviolet light producing lamps mounted in a photochemical reactor are continuously cleaned, while a reaction is being carried out, by containing a large number of small, chemically inert plastic pellets in the reaction solution. The plastic pellets are dispersed in the reaction solution and maintained in turbulent motion by a stirrer in the reactor. In use, the pellets frequently impact the outer surface of the tubular wells with sufficient momentum to prevent deposits of material, which could discolor the surface, from adhering on the tubular wells.