seems to be lots around but what works. other than stripping it out and redoing it lol
ah, that's what I was going to suggest
lol 😉
bleach, toothbrush, rubber gloves, attractive assistant, uniform,
well maby just first three, experiment in hidden area
hydrogen peroxide seems to be the thing i need according to google lol now where can i buy some without looking like a bomb maker 😉
I use spray bleach...pretty strong stuff with a lovely 'reminds me of swimming pools' smell.
This!
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Second the Dettol Mould and Mildew cleaner. Recommended to me once and its amazing. Rather oddly I tried another brand once that appeared to be the sameish stuff but it didn't work. If your grout is bad then leave it on overnight. It says only leave on for 5 minutes but I've never had any problems. Also cleans up your sealant a treat too.
Don't use grout pens, they are beyond rubbish!! Just tipp-ex in another bottle!
Borrow a steam cleaner from somewhere
Try a steam clean first. If this fails, get a Dremmel and spend hours raking it all out.
When you regrout, or get the old grout clean, finish with a mould inhibitor.
cheers chaps