I used fractionation to remove free floating algae, and nitrate precursors in my couple of ponds, in conjunction with heavy plantings.
koi pond fractionation
As you can see, in the video above, fractionation removes everything from free floating algae, to fish waste, to invisible chemical compounds, as foam, that fall on the ground.
I also always figure (as in nature) the ratio of plants must exceed the fish load.
https://youtu.be/uyb3z-V1Rsg
The pond in the videos above was only above 500 gallons, and contained only about 5 fish
Beside aquatic plants like lilies and hyacinth, placing semi aquatic plants like Papyrus in shallow shelf areas around the edges also use excess nutrients the algae need.
The pond below was between 1500 and 1700 gallons, and was the summer home for about a dozen Uruguayan cichlids and their spawns
I also liked using elephant ear, but in WI, the short season kept it small.
The pond above used a similar foam fractionation.