thanks for your reply, we added more, and are going to check again, here before retiring tonight. I have been checking my filter pressure, and backwashing, thanks for reminding me though. I prefer alot of information, than not enough, LOL! I have kept with it all day, and been testing and adding, we are going for the 12% tom., it seems like it will be economical. I am questioning the potency of the Big Lots bleach, hard telling where it was stored/ Thanks again, hopefully we will see more of the bottom this week-end. I feel positive about it.