Toilet Pan water turning Brown/yellow a few hours after Flushing

[kofi2003uk]

hi everyone,
i need some advice please. past few weeks i have this problem where we flush the upstairs toilet and its all good. nice clean water. but come back to the toilet after a couple of hours and the water in the pan has turned brown or kind of yellowish /brown.

Toilet pan was replace about 6 months ago and it has worked fine until about 2 weeks ago when this started. seem to me some 'stuff' is draining back into the pan but why?
the back is fitted with a flexible connector. i checked the back of the toilet (back to wall) and i notice the flexible pipe connects from the back of toilet, dips down and rise to connect to the outlet drain pipe. so effectively the flexible pipe has sort of a U bend in it. i wonder if this could be part of the problem? am not too sure of this theory as the toilet was fitted 6months ago with no issues until now.

i poured a few buckets of water down the toilet in case it was a blockage. thought it had fixed it but after 2 days the issue is back.

any ideas please? and see the pictures attached. not the best picture but hopefully you can see the bend downwards in the flexible connector. thank you

 

[denso13]

That won't be helping and needs sorted. The dip will be half full of crap and seeping into the pan.

 

[kofi2003uk]

thank you for the fast response. i will get that raised then. i guess i can put some bricks or something underneath it to raise and level it with both the back of pan and outlet drain pipe. am guess raise it up and shorted it if possible.

any other thing to look out for whilst at it please? many thanks

 

[denso13]

Try that first and see if it helps. Better with a permanent fix but no rush if it works. Nothing else really.