Not much more than normal household cleaner in my experience.
Household cleaner and a toothbrush.
( TFD is sporting this season's finest necropants, Fri 21 Oct 2011, 0:16, archived)

I did try that, It's generally a huge build up of scum and mold on the pipe work mainly.
It improved it but there's still a lot there, just summing myself up for round three.
(DaftScrawl That's no moon, that's my mother!, Fri 21 Oct 2011, 0:18, archived)

Bleach and wire wool then.

( TFD is sporting this season's finest necropants, Fri 21 Oct 2011, 0:19, archived)

That's my sunday sorted :D
Cheers.
(DaftScrawl That's no moon, that's my mother!, Fri 21 Oct 2011, 0:20, archived)

ding ding ding
Round 2 of the fight of the century, gloving up is the new comer DaftScrawl, weighing half a tonne and with no real experience she is not the favourite in this match up.
In the other corner, a well known opponent, scurge of the bathroom, hard hitting, big guns, a mix of piss and mould! BACK OF THE TOILET SCUM!
( Windy Pig I'm naturally quite suspicious about the moon., Fri 21 Oct 2011, 0:22, archived)