I have a nice 1/4" carpet of algae growing on the sides of the pond. Never had string algae and sounds like I don't want any. Had green water last summer that UV took care of right away. But... last summer and this year I have tiny bits of suspended algae floating in the water. It is so small that my Nexus K1 static filters nor my AlphaBead seem to catch it. I've tried a 100 micron filter sock but the algae just dissolves and goes through it. Same with trying to net it out... it just dissolves when I pick up the net.
Water temp is 65F and I'll put on a shade cloth when the temps reach 70F.
Here is a photo (BDs are at 7 ft. depth). Looks good at first, but when you look close the koi look like they are in a freshly shaken snow globe.