Woke up to find a thin stream of water shooting 10 feet up in the air. The flex hose between the pump and the filter had developed a pinhole leak. After removing the offending hose and scouring the local hardware and pool stores, I finally found enough pieces to make repairs. I have two elbows with one threaded end and 1 slip end, 1 union with two slip ends, 1 elbow with 2 slip ends, and spa flex pipe cut to fit. I dry fit the pieces together and opened the valve to the pump so gravity would start to fill the filter. Of course, there were leaks at every joint. What do I need to do to prevent leaks when I glue the pieces together? Are there any tips or techniques for making the threaded joints leak free?