I posted this few years ago but didn’t get much input. Your closing your pool - it’s all vacuum and ready for slamming and algae 60 if you use it. I think if your using algae 60 this trick will work for sure. It’s only for filter cartridges or if you can by pass the sand & DE filter. Take out the filters and run pump with chemicals! I noticed using Alg 60 most of the chemicals get into the filter and not in pool water.