I originally posted this in Questions and Observations but maybe this is a better place.

Yesterday in my small pond (25' X 50' X 4' deep) the water was green (planktonic algae I presume), visibility about 20". Pondgrass covers about 50% of the surface (will be thinning out this week) and very little filamentous algae. Today the water is clear, visibility 4'. What happened?

In the bigger pond (1/2 acre, 6' deep) the water is still green, visibility about 22".

Since I have LMB, BG, CC and mosquito fish in both, I would like to maintain some bloom. In the larger pond I have an ongoing duckweed problem and black layer muck. I've been told adding microbes may help. I'll do that later this week. I add aerated well water at least every other day although haven't done so for a week. How will the microbes effect the aglae bloom? Should I still add them to the little pond that has cleared up?