Quote Originally Posted by -MARWOLAETH- View Post
The light colour is the grouts base colour for the darker I added some black acrylic.

Are there any sealers that wont make it shiny?
Should be able to find some matt clear coat sealer at B&Q/Homebase/etc, but it won't be as matt a finish as you have now. For long-term durability I'd go with a coat of sealer.