Dark red/brown/orange spots

[whats_shakin]

Hi all,

6000 gallon gunite pool, ~50 CYA, good chlorine and pH levels.

I've noticed the past few weeks these dark red-orange-brown spots appearing in my pool that do not brush out. Water is crystal clear and pH/cc/fc/cya are good, so I'm going to assume it's not algae.

TFP pros, what's causing this? Out of whack alkalinity? Mineral build up? How do I fix it?

Thanks in advance!

 

[PoolStored]

Take some vitamin C pills and see if they remove the stain. You can use directly, or put in a sock and scrub over the area. If they go away, it is iron staining, might be due to rebar ties (wire used to hold rebar together) that are rusting underneath.

If that doesn't work, follow our stain guide...

Stains in Your Pool

The stained pool is beyond embarrassing. Our in-depth Guide to remove stains in your pool will help you to remove the stains and prevent them in the future.

www.troublefreepool.com

 

[whats_shakin]

Okay, follow up. Got a bunch of vitamin c tabs and put them in a sock. Ended up holding the sock full of tabs over one of the stains, it definitely lightened up significantly but unfortunately there’s now a dark mark where the sock was being held (see pic).

There’s also something like a dozen of these brown-orange spots all in the deep end, so not sure if holding a sock against them is really doable especially if it’s leaving a dark mark in the lining.