David, Theo,

The beveling and gasket lube sound like great ideas. Will it stay on and not turn even if only pushed on like the buried stuff, or do I need PVC glue on this 15-inch elbow? Pardon my ignorance, I have never used this type of pipe before and the contractor who built the pond did not use glue on the pipe. Also, I have never come across anyone selling this large size pipe. Any suggestions how to Google up a local vendor?