try aquarium silicone, it's safe, and meant to seal glass. I found some on amazon... http://www.amazon.com/gp/product/B0002ASD2K/ref=oh_details_o03_s00_i00?ie=UTF8&psc=1 been using this on my leaky Kathy recycler welds, so far one application has been holding, but I am sealing up pin holes, you...