I was on my way back from work and knew I needed chlorine for my pool, so I stopped at Family dollar store to buy some bleach. It's the easiest to stop at place by a long shot for me. I've had good results with their bleach before. 6% meant around 5.2. So I bought the last two gallons on the shelf of it to make up the 48 oz I would need. Got home. Tested the water. Added what I figured. Waited an hour. Tested again. Came up with same amount. Tried testing again, but same. Not having any distilled water, I just mixed half of the bleach and half of pool water and tested. Came out almost zero. Tested with 10ml of straight "bleach"... ZERO. Pink with the powder? No. Nothing! Be warned! Lucky I had some cal hypo tabs and my calcium is low enough. I bought bleach a week ago from them with good results. Now their bleach is nothing more than water and NaH. Sure raised my pH. They may have ran out and found some in the back that's old as me.