I have an above ground pool 17x29. Getting yellow staining on skimmer and ladder along with streaks on the floor and walls. Been using the pucks since weather is cold. Pool temp now is 80. Was 68 this past weekend and 72 last 2 weeks. MN weather.
Where do I purchase the absorbic acid?
And the sequestering agent? Local pool store?
Also have a mustard algae problem?

Drained pool the beginning of the year and refilled. Could that be the staining problem?

I use liquid chlorine 12% as shock. can I use that to bring chlorine up or reg bleach.

Kids want to have a pool party end of the week. Can they swim while it is being treated?