I Have No Clue... Clear Oily Residue on top of water

[RobinsonFam92]

Hello,
I've had a pool for the last 15 years. Never seen this issue.

This morning when I went out to look at pool there were dark circles on the bottom. Upon further investigation it was actually shadows cast by something floating on top of water. It was concentrated in the line where the return jet shoots the water out. When I turn the pump off they disappear, but when I rub the sides of the pool I can see them dispersing into the water again. So what ever it is, it clings to the side.

Background: new liner, no swimmers yet (so no sunscreen or hair products) we've had a lot of rain this week.

FC:3
Cya:30
PH 7.4
ALK: 120
Cal. Hardness 200
I use bleach for shock

Hayward Pump that is 1 year old and sounds like it is running fine. Sand Filter

I never go to the pool store, but called one this morning to discuss this issue. They said Phosphorus and Nitrates can cause this. And wanted me to bring a sample in. I can imagine myself walking out of there with 200$ worth of chemicals.

I wanted to ask here first.

Thanks for any help
Melanie
( I could t create a signature with my phone, will try to do that later)

 

[OTPirate]

Hello! Can you send a picture?

 

[RobinsonFam92]

Well I don't know if you can see it I'll also attach one more


It's the dark blue circles

 

[RobinsonFam92]

It wouldn't allow me to upload another. Here a link to another Imgur: The most awesome images on the Internet

 

[Richard320]

Sounds like maybe mold release or oils used in manufacturing.

Try a scumball. The pool store should have them, and this time of year, maybe even walmart.

Phosphates and nitrates are boogeymen to scare up some sales.

 

[Mr Bruce]

Another thought is to put an old t-shirt over a leaf net, suspend it in front of a skimmer and brush the whole pool with the pump running. If the t-shirt wasn't fine enough you could stuff paper towels in the skimmer. Be sure to not go far if you try paper towels, you don't want it to clog and starve your pump. Just for good measure you could bump the chlorine to just slightly higher than target to help it break down.

If I had to guess I would bet it's something they put on the brand new liner to clean or "finish" it.

 

[drharris]

I got my liner replaced this year and I had a similar issue. I suspect it was some kind of protectant on top of the liner while it's in storage. It was easier to see because pollen would clump up to it. I used the hairnets inside the skimmer basket (https://www.amazon.com/Disposable-Hair-Spun-Bonded-Polypropylene-White/dp/B002XK2FS0). I also draped a hairnet over my skimmer pole and went at the water a little each day. It eventually came out with a week of doing both. Also second the Rola-Chem scumbug idea - I know it works well for sunscreen and lotions, so it may work here.

 

[Swampwoman]

I believe this is a known new-liner phenom where the emulsifiers leach out a bit for the first little while...read about it somewhere last year when I was getting a new liner. Didn't happen in my case, but suspect the scum ball or fabric will clear it. You might ask the mfg.

 

[RobinsonFam92]

Thanks for all the replies. I thought about trying to catch it in a shirt or cloth. Also looked at the scum bugs. I will try this! Would you think it would be safe for the kids to swim in?

 

[drharris]

We swam in it and nobody got sick, so I assume it was ok! I think splashing around moves the residue around enough to where it isn't easily ingested by the kiddos. You could try to start catching some with an old shirt on the skimmer net if you're worried.