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I gave you WRONG info on the PPM. It's 4.5 PPM NOT 12 PPM. Â Â SORRY!!!!!If you're using bromine, chlorine WON"T show up ... bromine converts chlorine to bromine.
I'm using dichlor, but some of my test strips have a spot for Bromine and that did change along with the MPS, event though its been nearly 2 weeks since I used MPS.
So, should I superchlorinate and see if I get a reading?I've only ever used test strips and they have worked fine.  I usually only test weekly or less.  I tried a few different brands and nothing registered.
Hmmm... I just did an experiment.  I added 1 TBS of dichlor and then about 1 minute later I tested in the filter box, the color was dark purple.  A couple minutes later I added 1 more TBS and then tested the general water area.  The color was white.  So I tested in the filter area again... and white.  So this leads me to believe that it is bleaching the test strips.  I'm leaving the cover off for a bit and will test again later.  I think I'll put it in my plans to change the water soon.