Today I did the Ph Decrease in-a-sock and the Vitamin C tablet check. It seemed like the sock didn't take much of the stain spot away, but the Vit. C melted a hole into the middle of it. Like I've said before, we treated for mustard algae 3 times and nothing has changed. What do I do if this is iron? My readings at present are:
Total Hardness = 400 ppm
Free Chlorine = 0/0
Ph = @7.8
Total Alk. = @160
Cyanuric Acid = 30-50
This is from an HTH test strip. We were told, too, that our chlorine would always read low because we have a Frog System on our pump.
Thanks