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I agree with Bill -- your pH drift is more likely due to other factors than small dichlor doses. Using household bleach instead of dichlor will slow the build-up of CYA, but I'm not so sure about TDS. I seem to recall that bleach has a lot of dissolved salts. If you are comfortable with the handling and safety issues, given your low pH problems, bleach shocks sound like a good idea. I also think the shelf life of bleach is relatively short, so watch the potency -- inadequate shocks actually add to combined chlorine.Raising TA could help buffer pH changes. Since you are seeing drift down, try running at the higher end of the range. If your "pH Up" is sodium carbonate, consider using baking soda (bicarbonate) instead. It will raise TA, along with a lesser rise in pH.
There is not really that much of a difference in TDS between bleach and Dichlor.Bleach = 1.6 TDSDichlor= 1.8 TDSIf you decide to use bleach for shocking premix it with water before pouring it into the tub.CapMorgan