I want people to see that running ice cold water all winter does not hurt the fish, and that koi are not tropical as some are lead to believe. THERE is no such thing as koi getting burnt gills from ice cold water, simply not true what so ever! It bugs me that people are afraid to start to start up the pumps in the spring for fear of freezing the fish, while mine run all winter, for the last 23 years and never have I ever seen that in winter. But I have seen burnt gills in the summer many many years ago, when my bottom pond was very small, the waste from the top ponds used to all dump in a much smaller bottom pond, and the water conditions were bad in that pond, and all the small baby fish that got threw and lived down in that way too small bottom pond years ago had burnt gills from POOR WATER Quality, not ICE COLD Water, cause it was SUMMER! This is why it is important for people to get their pumps back running very early in spring, and not worry about how cold the water is! My water is still below 40 Fahrenheit, and was much colder in dead of winter, and my fish are just fine!