Coloured grout grout cleaner advice needed

[Nevernamedchanged]

Can anyone recommend a product that gets rid of mould on coloured grout? Most products seem to contain bleach but our grout is grey and I’m worried a bleach based product will leave white marks which will look no better than black marks. Has anyone used hg grout cleaner on coloured grout?

I use viakal on my grey grouting and it’s been fine.

Thanks @Babychewtoy was a bit worried it would bleach the grey.
Also aware I may win todays dullest post so thanks for replying