Designing a Pond Canopy to Keep the Leaves Out?

My husband and I have had a goldfish pond for many years. Ours is a medium size, ~1500 gals. What we do is use scrap 2x4's to create a shallow A-frame type support to which we staple window netting (which comes on long rolls) or sunscreen netting (which is wider), after being sure to pull it taut The leaves will blow off and away and rain and sun can still get through. If you need to overlap pieces of netting, overlap from the top so that leaves slide down and off, not down and under your edges.
Note, if it is not taut, leaves will accumulate in the hollows and when wet will become quite heavy. We have heard of frames being made of PVC instead, but haven't tried this.

We tried bird screen type netting originally but were not pleased with the results. Leaves would catch in the holes, and the wind would eventually force them through (when wet) or break them up and pieces would fall through when dry. Good Luck! mc
P.S. the netting and framing pieces will last for several years, and it only takes us part of an afternoon to put it together.