B-well :

What does the green algea look like , how much rain over what period , what was visa. before the rain , how much fert. did you use before and what type , did you lose top part of water out of the lake via outflow ? It sounds like you lost your bloom because of excess new water. Often the bloom will come back in a few days . You have to be careful with fert. in late summer. Post back with more info and I will try an answer. ewest