HI GUYS,
MY POND IS IN THE NORTH SO MAYBE THIS WON'T MEAN ANYTHING FOR YOU GUYS BUT I RUN MINE ALL YEAR. IN THE WINTER I MOVE THE STONE TO A DEPTH AROUND ONLY 3 FT . IN THE SUMMER I RUN IT ONLY IN THE EVENING AND NIGHT. SOME OF THE OTHER GUYS ON THIS SITE HAVE PONDS IN TEXAS AND WOULD BE MORE KNOWLEDGABLE THAN MYSELF ON THIS.
I AM SURE THIS SITE WILL HELP YOU BOTH A GREAT DEAL AS IT HAS HELPED ME.