Had an algae fun time Aug 2013 one year ago when I departed for 3 days and left the back wash valve up.
Yes, I did that. You guys helped me fix it. Was a mess.
Various white plastic parts turned yellow, like skimmer floats.
Now pool is clear and all is fine but the previously white plastic remains kinda yellow. Some of it wipes off with a rag but hard to get out of small spaces.
What is this stuff?
How to remove?