Bathroom sealant that works/mould problems!

[pinkytea]

I wasn't sure if this is best place, so please move if not.

I have a major problem in my bathroom with the sealant.
I have to keep re-doing mine every few months,
a) because it starts peeling or
b) because of the mould, both black and lovely pink mould that won't come off.

Q1
Does anyone know of a sealant that actually works? Perhaps a professional one?
Also is there a way of applying it so it looks even cos it always ends up a mess no matter what tools I try!!


Q2
One further question, is there a certain type of sealant I should use on the kithchen sink where the work surface joins the tiles on my wall behind the sink? Or can I use the same one?

I have the awful mould on mine, both pink and black types. Will try the bleach. :)