Brown spots on wall and floor of pool

[nima katy]

Hello All,
I recently built a pool and probably using it for the last two months. it has been a week+/- that I see 3-4 brown dots ( between dim and quarter size) on wall and floor of the pool. I am wondering if this can be related to chemicals of the pool.

 

[TinFoilHat]

What are your water sample test results? Your free chlorine is probably low and you now have algae. An overnight chlorine loss test will probably show that. This would require a SLAM to remove it. Your signature doesn't show what test kit you have. I'll link the ones we recommend as they give a true measure of your water which a pool store is hit or miss on. Please read about the SLAM and the CYA/FC relationship that might also be off in your pool.
FC/CYA Levels
Test Kits Compared
Overnight Chlorine Loss Test
SLAM Process

 

[nima katy]

What are your water sample test results? Your free chlorine is probably low and you now have algae. An overnight chlorine loss test will probably show that. This would require a SLAM to remove it. Your signature doesn't show what test kit you have. I'll link the ones we recommend as they give a true measure of your water which a pool store is hit or miss on. Please read about the SLAM and the CYA/FC relationship that might also be off in your pool.
FC/CYA Levels
Test Kits Compared
Overnight Chlorine Loss Test
SLAM Process

I do have 9.5 ppm Chlorine and zero combined chlorin. I just checked it with TFTestKits. My Salt level shows 3200ppm on the app

 

[PoolStored]

Can you post some pictures of the spots? That would help our diagnosis.

Brown spots may be from fertilizer, they may be rust spots, or something else.

Takes some vitamin C tablets and rub them on the spots (you can also put them in a sock and rub the sock over the spots). If the spots disappear, they are rust stains.

Again, post some pics.

 

[nima katy]

Can you post some pictures of the spots? That would help our diagnosis.

Brown spots may be from fertilizer, they may be rust spots, or something else.

Takes some vitamin C tablets and rub them on the spots (you can also put them in a sock and rub the sock over the spots). If the spots disappear, they are rust stains.

Again, post some pics.

 

[mknauss]

Obtain a strong magnet and see if it sticks to the spots. Could likely be wire ties from the rebar. You will need to discuss with the pool builder what they propose to do to remedy it.

 

[PoolStored]

Thanks for the pics. I concur with Marty's assessment.

 

[nima katy]

Obtain a strong magnet and see if it sticks to the spots. Could likely be wire ties from the rebar. You will need to discuss with the pool builder what they propose to do to remedy it.

If that would be the case, what can be solutions?!

 

[mknauss]

They vary. I do not have direct experience so suggest you speak with the pool builder if that comes to pass.

 

[nima katy]

They vary. I do not have direct experience so suggest you speak with the pool builder if that comes to pass.

Thanks for your feedback. Let mw check and i’ll get back with some answers

 

[nima katy]

Thanks for your feedback. Let mw check and i’ll get back with some answers

The PH is high 8.4 and it doesn’t go down. Can it be related as well?

 

[mknauss]

Not really.

Can it be related as well?

 

[PoolStored]

The PH is high 8.4 and it doesn’t go down. Can it be related as well?

No, rebar ties will rust independent of pH.

Lower your pH in .4 increments with muriatic acid. You might target 7.4. Add enough to lower pH by .4 and test again in 30 minutes. Continue to lower in .4 (or less) increments until you get to 7.4. With a new pool, it may need frequent muriatic additions for 6-24 months with new plaster.

 

[nima katy]

No, rebar ties will rust independent of pH.

Lower your pH in .4 increments with muriatic acid. You might target 7.4. Add enough to lower pH by .4 and test again in 30 minutes. Continue to lower in .4 (or less) increments until you get to 7.4. With a new pool, it may need frequent muriatic additions for 6-24 months with new plaster.

Thanks for explanation. Can this material be purchased from Home Depot or where is a good place to buy these?

 

[PoolStored]

Can this material be purchased from Home Depot or where is a good place to buy these?

Muriatic Acid? Paint store, ace hardware, home depot.

 

[nima katy]

Not really.

My pool maintenance guy is coming tomorrow and he wanted to use steel brush to see if spots can be removed . Should I allow that with my fairly 2 month old plaster? If it is rust it can temporarily solution but will come back , right?

 

[PoolStored]

I would not steel brush. Use the Vitamin C tablets. If that works, then it is likely rebar ties that are too close the surface and rusting. Yes it will come back. The builder needs to fix.