As I vacuumed this morning I noticed a ring around my pool at the water level. It is greenish brownish...Stain. It is not slimy or scummy....just a stain. It's not coming off at all.
I have been doing the MA all week. IL or so in the morning and have my return pointing up and the pump at high speed to aerate. The stain ring is much more pronounced at the end the water is jetting to.
Is this as a result of the 5L of MA I've put in so far?
Last nights numbers:
FC 3 (which I then shocked to 5)
CC less than .5
TA about 175
CYA is about 30 from what I can see but a full week has not gone by yet.