Pond Boss Forums AQUATIC VEGETATION Identifying plants Film over the pond

So everything I see on phytoplankton seems to be favorable as it consumes excess nutrients and produces oxygen for the pond. But how better is phytoplankton at this than the original problem, which was duckweed?

It seems the pond is more "alive" without the duckweed--more snails, more minnows, more frogs. I'm just hoping that if this is indeed phytoplankton, that it doesn't produce the same type of problem.