1 year old liner faded in deep end

My kind of unique wood frame pool (built myself from some old landscape timbers!) is barely a year old and when I opened it this year only the deep end of the pool was faded...pretty substantially....five or six shades lighter than the shallow end and side walls...I should mention the liner is dark blue and black in a swirl pattern...I am curious if the algaecide I put in at the end of last year before I covered it may have settled on the deep end and had a bleaching effect.....my chlorine and PH were ok when I closed the pool with a solid cover and chemistry wasnt bad when I opened it....just needed some chlorine....any thoughts out there?"

I can answer only part of the question. I know for a fact that PolyQuat (if that's the algaecide you used) is a very viscous polymer which means it disperses very slowly and I believe it is also denser than water (not positive on this last point). I know that it is recommended to keep the pump running quite a while after adding it so that it thoroughly mixes -- probably at least 8 hours.

What I don't know is if it's acidic. It does not appear to be, but I don't know for sure. If it were acidic and settled at the bottom of the pool, then that might explain it. You (or someone else with PolyQuat reading this) can always add some to filtered water and see what sort of pH comes up. Or take some pool water and add some PolyQuat to it in a small bucket and measure the pH change.

Sorry I couldn't be of more help.

Richard