I understand freeze up is not an issue for everyone. The condensation in my line builds up and increases my draw 3 amps. Then we blow out the condensation and the draw drops 3 amps. Consistently. That is a 16% increase in electricity usage for me. Not to mention the freezing up and the advantages power at the pond provides like RC mentioned.
IMHO, rotorary vane pumps usually provide the most CFM bang for the buck, but lack high PSI (which you don't need).
