Thanks i'll look into that overnight chlorine test.. its been running 48hrs levels all a little low... I'm running a super chlorinate today, had to get my salt levels up a bit, I'll retest water tomorrow or later tonight.
On the chlorine loss... the pool in the summer months gets ALOT of sun to the point where just using a solar cover can bring temps up to 90+ (not where i like it, but HWHL). I tend to run lower FC after a busy weekend and usually super chlorinate on sundays after the last dolphin gets out. Its been stable. I do however wonder about the metals in these detail lacking bags and bottles of miracle powders. Last year i was convinced i needed to Slam some shock in... and i battled some really strange black/orange substance on the liner seems that wouldnt even scrub off. I eventually used vitiman C tabs in a sock and had to scrub it.. it was the only thing that worked.