It's wasn't leaking at that point (thank goodness)...it was leaking at the larger black "nut" that holds than onto the main tube. I just took it apart...reseated the black o-ring and tightened down. no problems now.Oh when I install my pentair quartz sleeve try to install the adaptor outside the tube. I notice it was cocked to one side. Took about three tries and then installed into housing with no issues. If you visit the pentair site they have real good video instructional video.