I thought I had a pretty good system set up for water in the winter. However, the last couple nights have hit the lower teens and I'm concerned and could use some help. I have an aquarium heater in the water container and I'm using heat tape for the length of the pvc pipes. I have the nipples screwed into the bottom of the pipe. Everything is staying unfrozen except for the very end of the nipple where the metal piece comes out. It's frozen solid around that and it keeps me from being able to tap them to get water out. Any ideas on how to keep this from happening??? Thank you for anything you can offer and my apologies if this has been covered elsewhere. A link to more information would be appreciated if needed.