Your fish are not stressed by the green water. It does not bother
them at all. It hides them from us!

We waited out the green one year...took a while...plants finally
kicked in and the algae could not complete. BTW, we get some blanket
weed (string algae). The koi think it is a treat, so it is in our
streams byt not in the pond :} The blanket weed fails as well once
the vasculars get going.