I put a clarifier in my pool and when I got up the next morning there was all this brown scum floating on the surface and my skimmer was full of a brown frothy waxy substance. How can I fix this?

Question:

I put a clarifier in my pool and when I got up the next morning there was all this brown scum floating on the surface and my skimmer was full of a brown frothy waxy substance. How can I fix this?

Answer:

This is likely a type of brown algae or mustard algae that has a tendency to float. An algaecide may be needed to kill the algae and drop it to the bottom of the pool where it can be vacuumed to waste.