New in-ground gunnite pool in Michigan in July 2022. Filled with pristine tanker water. Our pool guy closed it in mid-November, 2022 with a mesh cover. He opened it in late-June 2023, and the water was almost perfectly clear, but the walls were covered in rust-like stains. (See attached photos…) The floor and the steps had no staining. Tested the water for metals, but none were detected. Couldn’t brush off the stains. Shocking the pool did nothing, which makes me think the stains were not organic. Our pool installer suggested using two bottles of Pool Magnet Plus; over two or three weeks, most of the stains lifted. Had the water tested again for metals—nothing. So we spent the rest of the summer enjoying the pool. As I lowered the water for this year’s pool closing, I can see light staining still exists where the heaviest stains were in June. The pool guy used a chlorine floater that he left in the water with 3” trichlor pucks last year beneath the winter cover, and he plans to do so again with this year’s closing. Could this be the source of all the horrible stains I had on the walls? Looking in our pool mechanical room, the chlorinator has a considerable rusty yellow stain that covers the entire interior of the PVC, which makes me wonder whether that floater in the pool was the culprit of all the pool walls’ staining. If so, I will need to make sure my pool guy doesn’t use that again this year. Any insights and help y’all can offer will really be appreciated!
Did trichlor pucks in floater stain the walls in my winterized pool?
- Thread starter ShawnJ
- Start date
- Jun 22, 2014
- 52,024
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Welcome to TFP! 
Take a Vitamin C tablet and rub it on a dark stained area. Let us know if that does anything.
Take a Vitamin C tablet and rub it on a dark stained area. Let us know if that does anything.
- Jul 21, 2013
- 65,181
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Welcome to TFP.
Pool Magnet Plus contains...
You have iron or copper staining.
Were any algaecides added to your water at closing?
Some Trichlor pucks like those from Clorox contain copper.
Phosphonic acid lifts the metal and Etidronic acid is a sequestrant that keeps it in solution. When metals are bound to a sequestrant they will not show in a metals test.
Pool Magnet Plus contains...
You have iron or copper staining.
Were any algaecides added to your water at closing?
Some Trichlor pucks like those from Clorox contain copper.
Phosphonic acid lifts the metal and Etidronic acid is a sequestrant that keeps it in solution. When metals are bound to a sequestrant they will not show in a metals test.
Can you show the system?
Can you remove the filter cartridge and show it before and after cleaning?
Can you remove the filter cartridge and show it before and after cleaning?
When I hang a stocking filled with stabilizer in my pool, I make an "X" out of two short pieces of pool noodle tied together. Then hang the stocking bag from the middle so it ca't get stuck against a wall. You might consider how to hang a floater so you never have it hit the wall.
And never,ever ever use Clorox XtraBlue pucks, ect.... they contain copper which can stain *sumpthin' awful!*
Maddie
And never,ever ever use Clorox XtraBlue pucks, ect.... they contain copper which can stain *sumpthin' awful!*
Maddie
- Jun 1, 2018
- 16,019
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Also reconsider your closing routine - there’s really no need to use pucks under the cover if closed properly & at the right time & opened at the right time.
www.google.com
Closing an In Ground Pool
Winterizing a pool is essential for keeping your in-ground pool protected during cold-weather months. This Pool Repair guide will show you how to do it.
www.google.com
Yes, the Vitamin C tab did rub off some of the stain.Welcome to TFP!
Yes, he did add an Algecide--something I never use during the months I have the pool open. Thank you so much for the information you shared; that really helps me understand what must have happened.
GREAT suggestion! Thank you!When I hang a stocking filled with stabilizer in my pool, I make an "X" out of two short pieces of pool noodle tied together. Then hang the stocking bag from the middle so it ca't get stuck against a wall. You might consider how to hang a floater so you never have it hit the wall.
And never,ever ever use Clorox XtraBlue pucks, ect.... they contain copper which can stain *sumpthin' awful!*
Maddie
- Jul 21, 2013
- 65,181
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
- Jul 21, 2013
- 65,181
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
I've never had a pool guy do that before this past year, which made me wonder if it might be problematic since my previous plaster pools never had staining issues like these on the walls. Thank you for your suggestion!Also reconsider your closing routine - there’s really no need to use pucks under the cover if closed properly & at the right time & opened at the right time.
Closing an In Ground Pool
Winterizing a pool is essential for keeping your in-ground pool protected during cold-weather months. This Pool Repair guide will show you how to do it.
- Jul 21, 2013
- 65,181
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
If fresh water is available then do Ascorbic Acid Treatment - Further Reading to lift the iron stains then drain the pool and refill and start over.
With closing coming you may want to do that next spring after opening the pool.
Then do not allow anything to be added to your pool that you do not know the ingredients of. Do not trust Pool Guys to look out for you.
With closing coming you may want to do that next spring after opening the pool.
Then do not allow anything to be added to your pool that you do not know the ingredients of. Do not trust Pool Guys to look out for you.
- Jul 21, 2013
- 65,181
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
Copper in Pool Water - Further Reading
www.troublefreepool.com
Never use any chemical that has Blue or Blu in its name. Those are code words for copper additives.
And that added copper to your water…
Ugh. This is so frustrating to discover. Thank you so much to EVERYONE here on TFP for your help.Copper in Pool Water - Further Reading
Never use any chemical that has Blue or Blu in its name. Those are code words for copper additives.
And that added copper to your water…
View attachment 534316
- Jun 1, 2018
- 16,019
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
If you choose to use an algaecide at closing go with polyquat 60
www.troublefreepool.com
Algaecide - Further Reading
www.troublefreepool.com
- Jun 22, 2014
- 52,024
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Glad to help. As a reminder, take a moment to update your signature with all of your pool and equipment info. See our sigs as examples. It will help later. If you are on a well, include that. Also be sure to add which test kit you use. Have a great weekend.
- Jun 22, 2014
- 52,024
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus