What is smelly brown sludge in toilet bowl?

[phoenixmac]

My wife says it’s a cross between a fat-berg and the creature from the Black Lagoon.

 

[Twowaxhack]

My wife says it’s a cross between a fat-berg and the creature from the Black Lagoon.

Sounds like she’s seen it. Very interesting

edit : I didn’t realize a pic was posted

 

[Slagatha]

My wife says it’s a cross between a fat-berg and the creature from the Black Lagoon.

did she happen to mention how to defeat it?

 

[Twowaxhack]

Try to find some Mule kick bowl cleaner.

Im not sure if it’s still made or not. It works !

 

[Zanne]

Are you able to fit your gloved hand with a sponge with a scrubby side down in to it? I take it you've removed it all before and it keeps coming back?

I wonder if something about the trapway shape is not self-scouring and is leaving some residue or something in that spot.