What will clean these porcelain tiles - from these horrible water marks

[mcluma]

We have these porcelain tiles, and we have a very deep rust/water mark on the tile.

My wife has used so many methods of cleaning, but to without the result she is looking for, other than taking out the tile and replacing it, what else can we try

Thanks
Chris
IMG_3434 by chris mul, on Flickr
IMG_3433 by chris mul, on Flickr
IMG_3432 by chris mul, on Flickr

 

[terryplumb]

Try wd40 and one of those spongy scouring pads.

 

[foxhole]

https://www.tilingsuppliesdirect.co...MIopmi3sqq7AIVlO3tCh3RnA6nEAQYASABEgIiGfD_BwE

 

[mcluma]

Will try that one- have you used it?

 

[JohnD]

you can add pictures to your post with Copy and Paste. No need to link to another site.

Rust stains can be removed with a Phosphoric Acid rust remover. I have a bottle of Jenolite liquid but it seems to be discontinued now. There are lots of other rust treatments on the market, many will just turn the stain black.

This one
https://www.toolstation.com/rustins...MI0b_yur2s7AIVSrDtCh3SiQdqEAQYASABEgLTwPD_BwE
seems to be phosphoric acid.

Read the safety date sheet. Use gloves, eye protection etc.

It takes time, so on a vertical surface keep applying it with a brush as it will run off, or tape some kitchen roll to the surface, wet it with the acid, and cover with cling film to prevent it drying. Clean up any drips or splashes immediately with plenty of water. Wash it away as soon as the stain is gone. It may damage some surfaces, including skin and clothes, and marble or other limstone.

I believe Coca-Cola also works, but is a much weaker solution.