Help! Did lightening strike my pool?

[gebirbou]

We have an above ground pool with a liner (salt water system). We arrived home from a few days away and noticed that all the plastic in the water was charcoal black: the stairs, the drain, and the skimmer. There is also a big section across the middle of the pool that is dark. Please see the attached pictures. The pool people are saying that it is lightening but could it be electrical?

Thanks!

 

[Bama Rambler]

I've never seen lightning do that.
Does it clean off?

 

[Jimrahbe]

G,

Anything electrical would have popped the GFCI before any damage was done..

If this were my pool, I would be assuming it was struck by lightning..

Edit... I thought this might be lighting only because of the burned mark by the power cord plug... I could not really tell what the black stuff was, but assumed if it was algae you would not have asked the question... But, we all know what assuming can do to ya..

Thanks,

Jim R.

 

[gebirbou]

Thanks for replying. We tried to clean it off and some did come off (see attached pic of stairs). We brought a sample of water to the pool store and the water was perfect. No algae or other problems.

 

[JamesW]

Looks like black algae. Is it slimy?

I don't see how lightning would cause it.

Maybe someone threw something in the water?

If you wipe it with a white cloth or paper towel, does it transfer?

If yes, is it blue/green and slimy like mold?

Maybe soot from a fire?

 

[gebirbou]

Hi James,
The water was tested and it is not black algae. It is not slimy and the water quality was tested and is good. It does not come off.

 

[gebirbou]

G,

Anything electrical would have popped the GFCI before any damage was done..

If this were my pool, I would be assuming it was struck by lightning..

Edit... I thought this might be lighting only because of the burned mark by the power cord plug... I could not really tell what the black stuff was, but assumed if it was algae you would not have asked the question... But, we all know what assuming can do to ya..

Thanks,

Jim R.

Thank you.

 

[JamesW]

A water test won't detect black algae. It sort of looks like black algae but not completely.

Maybe soot from a fire?

I don't see any way that lightning would turn everything black under water.

Maybe a metal. Do you use a zinc inline anode?

Has copper or silver algaecide been used?

Is it well water with manganese?

Sprinkle some ascorbic acid (vitamin c) on the steps to see if anything happens.

Did anyone use the pool while you were gone?

 

[PoolGate]

What are those stairs made of?

 

[gebirbou]

Hi,
The receptacle burnt that is why I do not suspect black algae. No fire and we did not use copper algaecide. I attached the picture of the receptacle.
Thanks,

 

[gebirbou]

What are those stairs made of?

PVC I think.

 

[gebirbou]

I've never seen lightning do that.
Does it clean off?

No, it does not.

 

[JamesW]

Pour some muriatic acid directly on the step in a small spot to see what happens.

Try vitamin c.

 

[gebirbou]

Pour some muriatic acid directly on the step in a small spot to see what happens.

Try vitamin c.

Pour some muriatic acid directly on the step in a small spot to see what happens.

Try vitamin c.

Thanks. My concern is the burnt receptacle that is leading me to believe it was lightening or some electrical issue.

 

[JamesW]

How would lightning cause the problem?

How would an electrical issue cause the problem?

If lightning hits something like wood, it can burn the wood and cause black burn marks.

This isn't what's happening here.

The parts under water are not burned.

Something had to get in the water that plated out on the plastic.

I don't think that it's black algae.

It doesn't look like any typical metal stain. Even if it was metal, it would take a trigger event to make it suddenly plate out like it did.

I suspect that we're missing a critical bit of information about something that got in the water.

I would try muriatic acid on a spot and ascorbic acid on a different spot.

 

[ajw22]

That is a 15 amp outlet. What type of pump is plugged into it? Post a pic of the pump data plate. That looks like overheating due to excess current draw.

 

[PoolGate]

PVC I think.

Since PVC is non-conductive and they are underwater, it is not likely that is charring. Not to mention the PVC would probably melt first.

 

[gebirbou]

That is a 15 amp outlet. What type of pump is plugged into it? Post a pic of the pump data plate. That looks like overheating due to excess current draw.

Hi,
Here is the pic if the pool pump data plate.
Thanks,

 

[ajw22]

13.5 amps motor on a 15 amp circuit is overloading the circuit. You should never put more then 80% load on a circuit. 12 amps on a 15 amp circuit.

How often you run the pump at high speed vs low speed?

What amp CB and what gauge wire is feeding that outlet.

 

[gebirbou]

13.5 amps motor on a 15 amp circuit is overloading the circuit. You should never put more then 80% load on a circuit. 12 amps on a 15 amp circuit.

How often you run the pump at high speed vs low speed?

What amp CB and what gauge wire is feeding that outlet.

Not sure. I will check.