So we just started up our pool last Wednesday and thanks to all the help on this site, it seems like our water is on track. But one thing I did notice was this brown stain in the deep end. The attached photo is from the 3rd day and it hasn’t come off with brushing. I find it hard to believe that it was a leaf, but I’m new to all this. I’ve read the stain article and I’m going to try the suggestions shortly. My wife is kind of worried that this is some sort of underlying issue like with the rebar or something. Our pool builder is coming by shortly to finalize something and we’re going to point it out to him. I want to be educated in case he gives us some nonsense and tells us it’s not a big deal. I didn’t add a sequestrant during this start-up period, is it ok to do that still?
