Light yellowish staining after SLAM/Fiberglass

tam87 · Feb 10, 2015

Hi All, Just completed SLAM last week, levels looking good, I added a bit more bleach a few days ago per advice on my other post to help raise chlorine since I have SWG, but today developing a light yellowish/brownish stain on smooth areas--doesn't seem to readily come off? Any ideas??
Water is crystal clear and these stains definitely were NOT present before today!
FC-6
CC 0
PH 7.6
TA 90
CH 190
CYA hovering around 90

Thoughts?
Am going to buy some refills from TFT --do I need to get some other test beyond whats in my Taylor kit for this issue?

jblizzle · Feb 10, 2015

The only thought would be metal staining, but that would have been more likely to happen during the SLAM at high FC levels than after you let the FC drop back down.

You should not need any additional tests that those in the kits we recommend. FYI, it is highly likely that tftestkits.net will have a sale on refills in about a month (not sure how desperate you are).

tam87 · Feb 10, 2015

So how do I get rid of them? Thanks for the tip BTW on upcoming sale!

jblizzle · Feb 10, 2015

Well, first you need to ID the stain. Try putting a vitamin C tablet on the stain, if it lightens in a couple minutes, that would confirm iron staining.

tam87 · Feb 10, 2015

Ahh yes--did the Vit c tablet test and it came right off! Saw the article posted that describes the Ascorbic acid treatment, but I don't want to take my chlorine back down now that I have everything cleaned up! Grrr. Do these stains cause any long term harm if I wait to remove? Do they ever go away on own?

Or I could scrub my whole pool with Vitamin c tablets ! LOL!

JasonLion · Feb 10, 2015

No, no long term harm. The only impact is visual.

smforte · Feb 10, 2015

Tam87, see my post on metal stains. My fill water doesn't have metals and I'm thinking folks that owned pool before me must have put some kind of Algaecide containing metals in the pool. I've done the AA treatment a few times and use a Metal Klear on a weekly basis to keep it at bay as well as tad lower ph. Good luck w that!