Has anyone on here seen that polyquat makes a difference when closing with a mesh cover before the water temperature is below 60 degrees? If it can make a difference, is it best to add it at half SLAM level or at full SLAM level so there is more chlorine in the pool after it is added. Last year, I closed at SLAM level without adding polyquat with cooler water temperatures and opened up to significant algae with staining because of the mesh cover and mild winter. I’m closing in 5 days with 67 degree water so I’m planning on adding polyquat this time. I just need to know if I would have better results if it is added at 1/2 SLAM (8 ppms) or at full SLAM (16 ppms). I am also wondering if it would help if I added some chlorine or more polyquat in a few months if we end up having another mild winter like last year.