This is my third season running the TFP method but first with a SWG - converted last fall.
About 10 days ago, I was out of town, had issues with the SWG, FC dropped to 0, and my wife came home to some algae spots in the pool. Being out of town, I took the easy route and had her shock it 2 days in a row while brushing it. It cleared up pretty quickly and looked good for the 4th of July save 2 small fist-sized dark spots that wouldn't brush off. I wondered if they weren't rust stains but had not yet gotten a chance to do the Vitamin C tests.
Fast forward to today. We were away from the house yesterday and I went out this morning and see the attached picture. I tried brushing the stains and nothing. They do not budge. I even took a stiffer brush to the ones on the ledge and scrubbed good, still nothing.
I have not gotten a chance to test the water yet this AM, but my last test was about 2 weeks ago and showed:
PH 7.8
TA 75
CYA 45
CH 425
Salt 3400
I don't have any pucks to test if those stains are chlorine - I need to go pick some up - and am thinking a SLAM is in order ... but what about those "stains"?
About 10 days ago, I was out of town, had issues with the SWG, FC dropped to 0, and my wife came home to some algae spots in the pool. Being out of town, I took the easy route and had her shock it 2 days in a row while brushing it. It cleared up pretty quickly and looked good for the 4th of July save 2 small fist-sized dark spots that wouldn't brush off. I wondered if they weren't rust stains but had not yet gotten a chance to do the Vitamin C tests.
Fast forward to today. We were away from the house yesterday and I went out this morning and see the attached picture. I tried brushing the stains and nothing. They do not budge. I even took a stiffer brush to the ones on the ledge and scrubbed good, still nothing.
I have not gotten a chance to test the water yet this AM, but my last test was about 2 weeks ago and showed:
PH 7.8
TA 75
CYA 45
CH 425
Salt 3400
I don't have any pucks to test if those stains are chlorine - I need to go pick some up - and am thinking a SLAM is in order ... but what about those "stains"?
