There are some really nice houses with a view of that lake. Wonder how they like seeing that from the back deck?

A friend had that in his pond and he put a harmless blue dye in the water to reduce the sunlight and it killed the algae.





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Definitely filamentous algae. Dye will work. It is clear water that allows the sunlight to penetrate deeply that initiates the algae. Dark water prevents it. I cannot prevent the water from being clear because I have 6" wells with 20-25 hp submersible pumps putting water into the ponds all the time I am pulling out of them irrigating crops. So, the dye won't work for me.

Fertilizing a pond with pond fertilizer will create a "bloom" that will turn the water very dark and prevent it, also. But, once you've got it herbicides are usually necessary to beat it back. Then, the preventive measures like dye or pond fertilizer can be used.