Thanks bill d and bill c for the responses. Bill cody its funny u said that becsise i noticed by water quality aka visibility actually went down quite a bit and never really got much better. I did see a big differences in algae and weed growth. I called company and asked if its possible if they could fall over on its side and they said no. Im willing to bet you are correct. It is an older pond and never got attention much until i bougjt place almost 2 yrs ago. What do you recommend i do. Should i leave one in at around 4 to 5 feet of water for winter. If so when should i run it.