I think I'm still oxidizing things, since the Cl dropped overnight, and dropped from 5 to 4 from 3 hours ago. Should I shock to something like 8 or 10 and see what happens to the black areas?
Opened pool 3 days ago. Everything great until today - black marks on bottom
- Thread starter DivingIn
- Start date
That what I would suggest but I encourage you to get CYA (30 ppm) in the pool first
Chlorine can be quite aggressive without CYA .
So, CYA to 30 ppm and FC up to about 10. Then keep it about 10 ppm for at least 2-3 days to see if that works.
YOu are basically SLAMming the pool but in a simpler way. Let us know the results.
Here's what happened yesterday - I poured a gallon of liquid chlorine into the deep end. It traveled down to the bottom and the black areas instantly disappeared. After about 10 minutes, they reappeared.
- Jun 1, 2018
- 16,109
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Did they look the same or different?
Do you have new pictures if the stains look different?
If they look the same it might be something under the liner.
If they look different, they might be copper stains.
- Jul 21, 2013
- 65,848
- Pool Size
- 35000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-60
No, metals.
The pH change from the liquid chlorine addition is lifting the metals then redepositing when the pH lowers again.
Organic stains won't go away and come right back unless it is under the liner.
Stains, in general, don't disappear and come right back, so that's odd.
Stains, in general, don't disappear and come right back, so that's odd.
- Jun 1, 2018
- 16,109
- Pool Size
- 26000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
The stains are in the exact same place. The liner looks faded and worn on the bottom where the stains are.
And now today the spots are completely gone.
If they were from under the liner, what does that mean? The bacteria or algae is somehow going through the vinyl?
If they were from under the liner, what does that mean? The bacteria or algae is somehow going through the vinyl?
Some stains are actually behind the liner, in between the wall or floor and the liner.
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mcewenindustries.com
Stains and Discoloration in a Vinyl Liner Pool
Struggling with stains in your vinyl liner pool? Discover expert tips and effective solutions to banish stains and discoloration.
blog.intheswim.com
What are the black stains on the floor of my liner and how do I get rid of them? | McEwen Industries
If you have black or grey cloud-like stains on the floor of your in-ground vinyl liner, they are most likely caused by bacteria that is living in the ground under your pool. Bacteria sometimes show up years after a pool has been installed. We think the bacteria can be washed into your pool area by
mcewenindustries.com
I see - thanks. When I have the liner replaced, what can I do to make sure this doesn’t happen again?Some stains are actually behind the liner, in between the wall or floor and the liner.
Stains and Discoloration in a Vinyl Liner Pool
Struggling with stains in your vinyl liner pool? Discover expert tips and effective solutions to banish stains and discoloration.
What are the black stains on the floor of my liner and how do I get rid of them? | McEwen Industries
If you have black or grey cloud-like stains on the floor of your in-ground vinyl liner, they are most likely caused by bacteria that is living in the ground under your pool. Bacteria sometimes show up years after a pool has been installed. We think the bacteria can be washed into your pool area by