Something no one has mentioned yet that you may need to watch out for in Michigan if you cycle your pump is freezing up during the winter. I had to make sure that my air lines drained well all the way down into the pond so that water would not get trapped in the line above gound/water where it would freeze and plug the line. Also, I use a Thomas pump, they recommend you install a heater on the pump housing so that condesation in the pump doesn't freeze the vains and break them on startup. I have so far found this unnecessary. I used the heater the first year but have taken my chances since then. No problems yet. I've never replaced my vanes in 5 years of running 8 hours per day.
