Fertilizer Stains in Pool

[J4CKBOLT]

I swam in the pool this weekend for the first time this season. Swimming with brush in hand to get those hard to reach places [emoji3]. I noticed on the steps in one area I had maybe 20 copper colored stains the size of peas from fertilizer. The brush did nothing to remove the stains. Does anyone have a recommendation to remove set in fertilizer stains from plaster pool surface? Preference not to partially drain pool but I guess I could...maybe muriatic or CLR?

 

[JoyfulNoise]

Did you try vitamin C (ascorbic acid) on it? Most fertilizer blends have iron compounds in them as a micronutrient.

Oh, and why are you putting fertilizer in your pool....TFP doesn’t recommend you do that

 

[J4CKBOLT]

Did you try vitamin C (ascorbic acid) on it? Most fertilizer blends have iron compounds in them as a micronutrient.

Oh, and why are you putting fertilizer in your pool....TFP doesn’t recommend you do that

Lol thanks for the tip and laugh. I am sure the discoloration is from iron in the fertilizer I used. Ascorrbic acid...something I can get from Home Depot, liquid?

 

[JoyfulNoise]

CVS or Walgreens or grocery store - Vitamin C tablets (1000mg per tablet....skip the rose hip flavored one ). Crush up a bunch, put it in a nylon and let it sit on the spot. If it’s iron, it will lighten up.

 

[J4CKBOLT]

Ok will try thx [emoji106]