just got test kit and learning how to use the kit it is at 80or lower by sticks defiantly not higher keep in mind i did a complete water change due to a liner change and this was the last week of apr. so i have been getting all levels to where they should be as i said just bought the kit so really learning how to use that i used strips before i tested with strips today (due to lack of time i test every day with strips) and the free chlorine was only thing that was high will do another full test tomorrow when liner was changed i added stabilizer so its been circulating 24/7 for about a month now as stated water is crystal clear just didn't understand the black in skimmer had allot of people over weekend so it very well could have been sunscreen and etc. had this every year store said algae but not seen anywhere else but in skimmer i don't think its algae from what i read on this forum this is a great site!!!!!!!!!!! thanks