Strange brown substance coming up into toilet bowl

[RishiB]

Hi all, I'm hoping someone on here will be able to help me with an issue I'm having at home. We've just returned from a week long holiday and have noticed that one of our toilets (a catalano toilet on a geberit frame) seems to have brown water coming up into the toilet bowl. When we flush, the water comes out completely clear and there is nothing left in the bowl. However, over time the water in the bowl gradually gets browner and I have no clue why. The toilet has been bleached and is completely clean and the water is flowing down fine so I don't think there is a blockage. Does anyone have any suggestions as to what the cause could be?

Thanks in advance!

 

[Laurie1987]

Following as I came here to ask the exact same question!