Hi all. We have a polyethylene tub we got back in 2020. Over the summer, we didn’t use the tub at all, so I just kept putting a little chlorine in it, and got lazy about testing the water. When we went to use it again, the chemistry was way off - super high ph and super high chlorine levels. I lowered the ph to 7.4, lowered the TA to 90, got the chlorine down to 4ppm. Used it last night and then had itchy bottoms after using it. Any ideas as to what’s going on? Thanks in advance!