I need to clear some grout residue on my tiles and have bought the mix from BandQ which I think has helped (though it has dyed my charcoal grout to a whiteish colour...!) but there is still chunks there.

Is there a better remover available, and also, what sort of brush/cloth should I use? I've tried a scrubbing brush, nail brush, grout brush, abrasive green cloth and none are overly effective!

Also can I dye the grout back to black/charcoal?

Hopefully these pics below will help with your responses.Tile2.jpgTile1.jpg

Hi Fazza,

Acid cleaner, wire brush and a lot of hard work. I have seen this before with very similar tiles, are they porcelain?

Good luck!

if its only 1 or 2 affected tiles then i would just replace the tiles!

Hi wouldn't recommend an acid cleaner on colored grout as it will bleach the color . with the amount of grout left on the tiles in the pics you may be better off removing tiles

Hi All and thanks for your help. They are glazed porcelain tiles yes. I had thought about using a wire brush but was unsure if this would damage/scratch the surface of the tile? I have already used a grout cleaner bought in BandQ and this has turned the grout to a light grey/whiter colour. Can I dye this back with a grout dye/stain?

yeah, you can re colour the grout, cant remember the product, enduro knows it though!

This company does a grout colourant Tile maintenance products, Universeal Sealants, Universeal Rapid-All-In-1 and these CSi:Grout |the latter being the one enduro posted.

Thanks guys, all very helpful? So apart from elbow grease, any more advice on best brush to remove? As I said worried about wire brush damaging tiles but if others say it's fine then happy to go with it!

I dont think a wire brush would scratch a porc tile but someone may advise different

Thanks guys, all very helpful! So apart from elbow grease, are there any more recommendations as to removal of the blotches of grout as I'd rather not replace tiles. Because of the texture there are a few sections on other tiles that have this problem where the grout built up so any recommendations on something to give a good scrub with are much appreciated!

Could try a clean piece of soft wood and a hammer to knock any remaining grout off the tile face.

What you need is Aqua Mix Phosphoric Acid substitute.. Go onto Ebay and type in Aqua mix, go down the page until you see Aqua Mix grout colorant click on this product, then go to visit shop and you will find it there.

Thanks enduro, you seem to be the go to guy here so thank you for response.

Once I've used the phosphoric acid substitute can I apply the grout colourant staight on or do I need to clean the grout first?

Originally Posted by fazza

Thanks enduro, you seem to be the go to guy here so thank you for response.

Once I've used the phosphoric acid substitute can I apply the grout colourant staight on or do I need to clean the grout first?

Use it to clean the grout too...Then you can use the grout colorant. I find csi grout colorant easier to use. Do all of the grout on the floor and you will find keeping the grout clean will be much easier