Thank you for the reply, PoolDoc! So the next time I see a film on the bottom I will bring chlorine to BBB shock values THEN brush. Thanks for that great tip!

I DO know my CYA levels - see first post - 60-70 right now. I've been following BBB for almost a year and never use the goops form the pool stores. I use a combination of feeder and liquid generic bleach. That's why I'm confused because I thought by following BBB and keeping things within the proper values this would not happen. However, it's possible I never totally gotten rid of the mustard algae and that with the intense heat we've been having it was able to come back somehow. OR when my pool light came off for cleaning it exposed a ton of algae spores to the pool.

I'll keep it a shock values until things clear. It was clearer today but tons of debris on the floor to vacuum.