Stains in skimmer???

[JimK]

Is it oily? I get a rim all the way around my skimmer. Weird that it's only in that one spot.

I get the same thing sometimes. I've read that it's from body oils, lotion, sunscreen, etc. I do notice it more if someone using sunscreen has used the pool.

It is odd/interesting it only occurs in the skimmer.

[FormerBromineUser]

I NEVER had that occur with my bromine pool for over 10 years. When I switched to chlorine, it began right away. I have always wondered about this.

[Anonymous [GDPR] European in the UK]

I get the same thing sometimes. I've read that it's from body oils, lotion, sunscreen, etc. I do notice it more if someone using sunscreen has used the pool.

It is odd/interesting it only occurs in the skimmer.

It tends to be more concentrated in the skimmers and therefore easier to spot against the white background. All fats/oils and body fats/sweat etc are a source for food for bacteria and mould (mold) and usually do form a tide mark ring. The reason I suggested a mould (mold) is that light gets in through the skimmer opening and generally only hits one spot at the back of the skimmer as in your photos so growth commences there.

FBU, interesting, can't make a suggestion apart from the bromine bank gave a higher residual disinfection level, only a suggestion.

[FormerBromineUser]

That might be it. I also get the gunk even when I have had no swimmers in the pool for over a week. It seems so strange that it doesn't occur in-pool at the waterline.

[JimK]

That might be it. I also get the gunk even when I have had no swimmers in the pool for over a week. It seems so strange that it doesn't occur in-pool at the waterline.

I did have it show up on the steps one time after a guest got in the pool after slathering up with a bunch of sunscreen, but other than that it only shows up in the skimmers. It has never appeared on the liner.

[FormerBromineUser]

Black goo, Jim?

[JimK]

Black goo, Jim?

Yes, greasy black goo.

Fortunately it cleans off pretty easily.

[FormerBromineUser]

Eeeeewwww! Skimmer is bad enough!