Oil / sludge residue on water line in skimmer

[mjc123]

Hey all,

I recently started noticing a dark grey sludge/grime on the water line in the skimmer. It doesn't appear to be showing up on the water line elsewhere around the pool, though it's harder to tell because the pool walls aren't white. In any case, it's truly "greasy" and when I rub it off with paper towel it smears. The first time I saw it I thought it might just be sunscreen residue, but when I saw it again a few days later with nobody having been in the pool, I started wondering if it might be something else - perhaps there is some kind of pollution in the air that is making it into the water? I even wondered if caterpillar droppings (seen some recently) or other biological waste (bugs - apparently they love dying in the pool) might cause it. What I am MOST concerned about is that there is something mechanical in the equipment - either pump, or filter, that could be leaking. I don't know anything about that equipement, but I posted about the filer leaking water in a separate thread (Sand filter trickle leaking - should I be concerned?). I'm hoping that the two aren't related in any way, but wondering if anyone might have had a similar experience

Thanks!

 

[Costas > DownUnder]

I have a brand new fibreglass pool - Installed late April but no one has swum in it as yet - Currently winter down here in Australia so water temp is hovering around 10 Celcius!

In the first few months of operation and balancing my water I noticed a similar scenario where a broad grey line would appear inside the skimmer box at the water line. It was always only evident where the water had flowed in past the skimmer weir and was hitting up against the skimmer internal wall. ie. Grey line was only on the internal skimmer wall housing and only towards the rear 2/3d's of the skimmer wall not towards the front of the skimmer and nothing around the entrance to the skimmer or the weir door itself.

This may point to it being some contaminant on the surface of the water rather than in the water..??

Mine was also greasy but would relatively easily wipe off with a sponge. I did not see any trace of this anywhere else in the pool ie. along the water line outside of the skimmer box.

In the last two months I have not noticed this grey line to appear any more.

Not sure why it has now vanished but it may have just been some impurities in my initial water fill or the initial load of dust/dirt/debris that was in the pool when it was first filled ...???

The only other thing that I have changed over that same period where it has now cleared was to bring up my calcium hardness level to around 225 - 250 as it was below 200ppm at the initial stages.

 

[ajw22]

When was the last time your sand filter was cleaned?

I doubt the grey sludge is coming from the equipment. It is likely environmental.

 

[cowboycasey]

it happens to almost everyone, scum, dirt, yucky stuff, sweat, oils, sunscreen, you name it gets collected in there.. I take a sponge full of dove soap and give it a good cleaning once a month or as needed, works great...

 

[rajung]

I have had this before, up to about 2 years ago before using something called a " scumbug", they go by different names, looks like a white floating sponge.
Took care of the problem totally, I usually use 2 of them through summer and toss when done for the year.
If its only in skimmer and water tests are fine, most likely the same thing I had.
If you decide to try them, just make sure to remove it before taking out the basket for cleaning, I did once and it got sucked through the line to the pump basket, I got lucky.

 

[mjc123]

When was the last time your sand filter was cleaned?

I doubt the grey sludge is coming from the equipment. It is likely environmental.

The sand was replaced last year according to the previous owner. Other than the occasional backwash, I have not done anything else to the filter this season


Sounds like I'm not the only one who has seen this kind of thing happen - it's just odd that it's only appeared in the past week and a half. I'll continue to monitor it and look into this "scumbug" thing!

 

[Killer95Stang]

Any fires in your area in the last few months? Right now in SoCal it is the height of fire season and it appears every fire bug (arsonist) has been in full force lighting fires lately. With that, we are getting a lot of ash floating around, which ends up in the pool and makes a similar type line in our skimmer. Since the skimmer collects a high concentration of debris from the surface of the pool and it sits floating in the skimmer, it tends to stain it. Using a sponge and a small amount of dish soap should help.

 

[mjc123]

No big fires that I'm aware of - a couple weeks ago there was one nearby, but long since out. However, it has been unseasonably hot.

Here are a couple photos of the skimmer that were taken today. Just yesterday I cleaned the same amount of sludge off and the waterline was clear - so these photos represent roughly 30 hours of time. The consistency is very similar to what I think of thick black grease, like you would use on an axle or other bearing. It has no discernible smell

Images:
http://u.cubeupload.com/mjc123/IMG3063.jpg
http://u.cubeupload.com/mjc123/IMG3064.jpg

 

[Pollock]

I get that stuff too and my pool is covered most of the time.

 

[rowiac]

I noticed something similar in my skimmer the other day, and Killer95Stang's comment about fires made me realize that must be it in my case. The Carr fire in Northern California is about 60 miles north of me.

 

[bmoreswim]

ScumBugs and Magic Erasers are about the same but different shapes. Scrub a bit with either for a clean skimmer. Keep them in there and it won’t get as dirty because it will scrub a dub as you swim.

 

[Killer95Stang]

you are right, that is a lot of sludge... The bright side is, it's all contained in your skimmer and not all along your tile line.

 

[DocEric]

Wildfires this year. That explains it for us. We’re getting some of the smoke from the Canadian wildfires here in Indiana.

 

[trafficdoc]

We have a newly constructed pool (<90 days old) and we've noticed it in our skimmer area as well. We live in Florida, we have a cartridge filter and our pool is in a screened-in lanai...so we have no debris/bugs/etc in our pool. Our dog swims in the pool with us from time to time though. I imagine it is body oils from us and the pup as well. We just wipe it off with a paper towel.