Rust on pool lights

[carnivalday]

Hi guys, long time no see! Ready to get back into the swim of things. I was walking around my pool the other day, and noticed some pretty serious discoloration around one of my lights. These lights face away from the house, so its easy for me to miss seeing it. Pool builder said I must have some metal in the water and suggested taking a water sample to be tested. I can do that, but this is only happening on one of my lights, so I would think its something to do with this particular light. Am I wrong thinking this?

 

[Texas Splash]

I wonder if there's a bad screw or something under there? It looks like something is rusting out/up from underneath. @JamesW, what do you think?

 

[carnivalday]

I was thinking the same thing. It looks like its coming up from the top screw. Pool builder says its the water. I dont know enough about it, but I would think if it were the water, it would be more than just one spot.

 

[Texas Splash]

Pool builder says its the water. I dont know enough about it, but I would think if it were the water, it would be more than just one spot.

Yes, unless the pH is extremely low to cause such corrosion, it seems odd. Plus I would expect corrosion all over. Curious to see what James thinks next time he joins us.

 

[carnivalday]

Its not pH. Ive been running 7.8 - 8.0 since the pool opened. Thanks Tex!

 

[Darin]

Painted surfaces don,t rust. You have either a failed paint seam or as it says above, a screw that is the wrong metal or not painted.

 

[JohnT]

While a bad screw is a possibility, this can be a sign of an electrical problem with the pool. With the bonding system doing its job, the rusting screws may be the only sign of current flowing in the pool.

 

[carnivalday]

I have a guy coming out Monday to check it out. Funny how I never even noticed it.