Hydroponic 3" Net cup holder

I made this after using a 3" hole saw to cut a 4" PVC pipe for a hydroponic garden test. The issue with 3" net cups is you need a 2-7/8 hole saw, not a 3". I got tired of the net cups sitting all loose on top of the pipe so I designed a bezel the molded to the pipe and gave a flat surface for the net cup to sit on. I then hot glued them to the pipe. I later realized that if I added a additional inner bezel I could place them on the pipe without using hot glue. I then added a "cap" for when I didn't have a seedling ready for the position to keep dust out and reduce evaporation of the fluids.