I had that problem about 2 weeks ago. I was trying to get my PH up, plus I had some new chemicals I was unfamiliar with...well.....to make a long story short, I went in one night without testing the water first, and got what was like a sunburn on my legs. Tested the water and everything was off the charts....sheesh. I am just now getting back into the tub...I'm kinda chicken...sure wish I knew what I was doing! LOL