My sink stinks!!

[FusionChefGeoff]

A really horrible musty / damp smell that gathers overnight or if we've been away. Tried bleach down it and overnight but still yuk.

A horrible bit of me is worried there's a slow leak somewhere and a big damp / mouldy patch behind the units but I can't see anything obvious under the sink.

Any ideas I could try?

Never allow anyone to pour cooking oil or grease down the sink.

Thank you!!! I can't physically remove the plug at all so replacing the whole thing would need an angle grinder or something to cut it out.

We are hoping for a kitchen refit in the next year so I will continue with a soda crystals ritual until then I think!!

If you can use soda crystals and white vinegar :)

Pour three-quarters of a cupful of soda crystals down the plug and leave for two to three minutes. Then, pour down a cupful of white vinegar (this will fizz up – the best part!) and leave for ten minutes

Another vote for soda crystals and boiling water. It seems to be the safest option and works for me. You have to keep topping up the soda crystals and adding more boiling water. It might take a few attempts but keep at it.

Soda and vinegar neutralise each other.

Oh my god just did mine