What is causing the surface algae growth is an abundance of organic waste in your pond. I would not suggest using any sort of algaecide on a pond this time of year as these treatments reduce the dissolved oxygen levels in your pond and that can harm your fish. If the pond has the possibility of freezing over, I suggest the use of an aerator of some sort instead of running a water pump as that will provide a lot more dissolved oxygen then say a water pump that is being used to just push water. There is an easy way to find out if your oxygen levels are okay in your pond by using oxygen test kits. The only quick fix I can suggest for the surface algae is the use of some sort of enzyme, like Microbe-Lift PL.
My advice for next season is to start prepping your pond for fall early (around late August) by using a fall program like Microbe-Lift Autumn Prep Winter Treatment and to also pull a water change of 30% and make sure that you have some pond netting over your pond so that leaves are prevented from blowing into the pond.
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