Hi,
My pond is 12ft X 7ft X 4.5 ft just started this April. I have 10 koi in the pond and are doing well. I have a heat pump and the water temp is set to 22 at the moment. As September is approaching I’m thinking of reducing the temp to 20 and thinking to follow a yearly pattern like : Sep 20, Oct 16, Nov 14, Dec-Mar 12, Apr 14, May 17, Jun 20, Jul-Aug 22. Please share your thoughts on this.
I am thinking of a winter cover for my koi pond covering the pond from mid october to mid March. I’m just thinking of building a wooden structure 3 inch above on the pond and then use the 25mm polycarbonate sheet to cover about two third of the pond and use 6mm clear solid polycarbonate sheet for the remaining one third for a better view of the fish. Please share your thought on this as I have to DIY in the weekends.
Thanks 
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