What is this?

[uvavi8r]

Pool is a Leisure Pool (fiberglass) and has been installed about 1.5 years. Over the past summer, we started noticing these silver/white rings in a few areas (around the jets closest to the pump). There is no ridge and on one occasion I found a small disk that could be broken (sorry no pics as my neighbor did the crumbling). I don't think it is anything going on with the shell other than staining. My bigger concern is that it is something coming out of the equipment. Sorry for the not so great pictures, the camera kept focusing on the water surface. The circles are a bit bigger than a pencil eraser head. I tried to remove the stain with a vitamin C tablet and it really didn't do anything. Any help would be greatly appreciated.

 

[ajw22]

@Texas Splash ideas?

 

[Texas Splash]

Those are not markings I've seen before. Can you explain a bit more about this small disc that could be broken? Could you also tell us more about the specific equipment you have? Your signature doesn't really show much, but you never know if more details will give us a clue. You could also post a pic or two of your equipment pad.

 

[ajw22]

Has any roofing or siding work been done at your house or surrounding houses?

 

[JamesW]

Possibly Osmotic Blisters.

What Causes Osmotic Blisters on Fiberglass Pools?

Learn how osmotic blisters occur and what can fiberglass pool manufacturers do to prevent them from occurring in the gel coat of a swimming pool.

www.riverpoolsandspas.com

How Do Osmotic Blisters Form on a Fiberglass Pool?

What are osmotic blisters in a fiberglass pool? How do bubbles form on a pool gelcoat? How can I keep my fiberglass pool from getting blisters? In this article, well discuss why pool blisters form, how it happens, and how you can avoid them.

www.riverpoolsandspas.com

 

[YippeeSkippy]

I would have guessed the end of a hose or something like that has dug into or marked up the finish?

 

[JamesW]

 

[JamesW]

Have you filed a warranty claim?

Questions to Ask Your Local Fiberglass Pool Supplier

Do the pools come with structural and surface warranties? (Your fiberglass pool should at least come with these warranties.)

Do the pools have a vinyl ester barrier coat? (This barrier coat prevents osmotic blisters on the pool’s surface from forming.)

At what thickness is the gelcoat applied? (The ideal thickness is 25-20 mls. At this thickness, the surface stays strong and flexible.)

Was the shell of the pool built on a level surface? (When built on a level surface, this prevents future damage.)

Is the gelcoat a solid surface? (When a gelcoat is solid, repairs are easier to make and far less noticeable.)

How to Find a Local Fiberglass Pool Supplier Near You

If you are wondering how to find a local fiberglass pool supplier and what to expect after selecting a pool company, we have done a bit of research to find the best pool contractors near you.

leisurepoolsusa.com

 

[uvavi8r]

Okay, here are the pics of the equipment pad



As for the equipment - Pentair EasyTouch 4 System Pool w/IC40 Cell 520593 - Pentair Clean & Clear RP 200 Sq. Ft. Cartridge Filter - Pentair IntelliFlo VSF Pump - 011056 - Pentair Master Temp 175K BTU Heater and there is the bonding element with a zinc anode element in it.

As for the blisters, as mentioned, there is ZERO elevation of the gel coat or any pool shell material, you can't feel where the staining starts.

There have been 2 houses (townhomes) that had the roofs replaced behind me in the past 1.5 years, the circles are smaller than a roofing nail head. The piece that I found the one day was black, looked corroded and had a metallic feel to it. By metallic feel I mean that it bent some of the black would crumble off and then it broke. I will see if I can find another one, as the original post said, my neighbor was SUPER curious and crumbled it before I got a picture (not helpful at all).

I have not filed a warranty claim as I wanted to see if it was something that was going on with the equipment, trees (I originally thought it was seeds) or something birds were dropping in. The only thing that makes me thing it is coming from my equipment is that the two areas that have the stains are in the vicinity of the first 2 return jets. I think I am going to put a skimmer sock on the returns and see if I can catch something.

Thanks for the input and recommendations, I will keep at it and see if I can collect more data.

 

[uvavi8r]

Okay - I finally found one of the "things" that is making these marks in the pool. Here are the pics both sides and a video (sorry couldn't load video on TFP)...not too difficult to break up and as you can see, leaves some markings when it is broken. I also am including my equipment pad, heater is isolated with a 3 way valve and the flu-vis check valve. The only thing that is in-between the filter and the return (now that I have removed the IC40 SWG) is the CMP "Pool Defender" water bond & zinc anode. I am beginning to think the pool defender is my culprit. Just wanted to post here again to see if anyone has seen something like this before. Thanks of for the assistance.

 

[Newdude]

That looks like something rusted, and zinc has no iron to rust, so it corrodes instead. (The white/chalky breakdown vs. the brown one)

The anode also doesn't do what they wish it would do for pools, so it likely won't even corrode.