I decided that I needed to seal the clay pipe on the bottom so I can take out the pipe without creating a swimming pool in my livingroom (somewhat of an overstatement but you get the idea). The best solution seemed to simply glue a clay plant saucer to the bottom with some constructuion adhesive.
After gluing the pipe I started worrying about the toxins in the glue… will is leach out into the water poisoning my plants?!? This kept me up at night, but I think I can solve this problem by just sealing off the bottom of the pipe with a layer of aquarium silicone so the water don’t make contact with the glue. Made sense in my head at least, hope it will work.