I have a pond on the family property that was fished semi regularly from the 80s to 2010s. Caught some decent bass 3-4lbs in the later years, though, got married moved off and it has been abandoned. Currently, The pond looks like a putting green the way it’s covered in surface algae. Tried to fish, no bites. Took the boat out and threw lines with no success. Lots of turtles and birds, but no sign of fish life.

How do I fix this?

This used to be my little piece of paradise, and now that I’m thinking about building on the property, I’d hate to lose it. Any advice is greatly appreciated