I have been using the methods on this forum now for 3 yr and been getting great results. This year I have something new to me going on. When I try and measure the Chlorine I put the 10 ml of water then the scoop in. It turns a little pink in parts and when I swirl it goes completely clear. This is 20 min after adding 6 gal of bleach to a 30,000 gal pool so I would think it would have some amount of chlorine at this point. I thought the chem might be old so ordered replacement reagents and I'm getting the same results. The normal test in a taylor kit shows that there is Chlorine in the pool. I tried diluting the water till it read 2.5 on a taylor then tried the fas-dpd test on the diluted water and didn't get a good reading.
PH was way low took 7 boxes to raise up and now a touch high at close to 8. Water is looking good with only a slight green cast to it so was thinking that a day at shock level would finish the job.