use only the plumbers goop. its now in a silver tube with purple markings. you can get it at home depot, lowes, and any hardware store like Ace or Westlake. Go to your local drug store and get a couple oral syringes for kids. they give them away at the pharmacy. tranfer directly from tube to syringe. You'll only need about a 1/2 in the syringe to do a pot. maybe 2. insert the plunger and gently push down and apply a small controlled bead. when done, pull back on the plunger to clear the neck, set it aside and let it dry out a couple days or so. youll then be able to pull the plunger out slowly with the dried glue, remove the slug, and you'll be able to reuse it. Its worked for me several times.