Rust coming through waterline tile

[Skiddy]

Started noticing this over the last few weeks. It’s definitely getting worse and it seems to be isolated to a single location on the edge of the water feature. The pool is a couple years old now from a new build. Any suggestions on the cause? I’m scratching my head a little but the only thing I can come up with is rusting steel structures behind tile?

 

[ajw22]

Rub a paste of vitamin C on the brown areas and see if it cleans up.

I doubt it is coming through the grout. I think it is on the surface.

 

[Skiddy]

Rub a paste of vitamin C on the brown areas and see if it cleans up.

I doubt it is coming through the grout. I think it is on the surface.

tried the V-C as well as some rust removing cleaners. It did clean up a lot of the running below and around the main rust source but there is one main grout joint where its very concentrated. After some research I am almost convinced it is rebar behind the tile rusting through. I contacted my PB and he said to try a Pool Blok PB-12 product to see if that will clean the rust area first and if that doesn't help he will come out and take a look.

 

[Skiddy]

If anyone else has had experience with rusting rebar through surface please chime in.

 

[Palpatine]

@Skiddy Did you ever figure this out?

I've got a rust mess on my skimmer tile and by my spa outlet... my pool contractor left metal exposed where it shouldn't be.

In any case, I can't be much help to you in your situation, but do mind letting me know how you ultimately got rid of the rust stains? Vit C didn't work very well for me either. I'm considering buying some pool patch and trying to grout over some spots... or maybe just painting the grout.

 

[Skiddy]

I think the PB is going to have to remove the tiles and ultimately seal off or remove the rebar that is causing the rust to come through

 

[JamesW]

It is probably efflorescence and it is bringing iron from inside the wall.

You can remove the tile to remove the iron and you can address the water getting behind the tile, which is why the stain is happening.

 

[duraleigh]

I cannot think of a reason why there is rebar (or any other iron) behind that location.

I agree it looks like efflorescence but that is a VERY odd place for the rebar to protrude.

I think you PB can fix it but it will not be an EASY job