Grout starting to crack already

[melodymaker67]

I replaced some tiles and stuck them down and re-grouted with "fix and grout" that comes in a tube. It acts as adhesive and grout.I did this a week before Christmas and already cracks in the grout are showing as if shrinking. Do I just keep re-filling/skimming or is this type of grout in a tube no good ?

Also, I went over mouldy grout with this after removing a little of the surface. I say a little as those jagged tools you buy don't really cut into the old grout very well and takes an eternity. Already the white is turning dark because it seems underneath the mould is starting to show. I would have thought that cutting off oxygen with the new layer would have killed it.

Thanks.

 

[Burnerman]

Sorry but I'm afraid you are learning the hard way, unfortunately.....that sort of grout is really grot, and the best stuff is that which is mixed from a powder - wasteful although that may be! Powder grout dries by chemical reaction, rather than by air. Best to scrape it out I think - maybe using a Stanley knife - and redo it.
Removing old grout is one of those jobs where you will lose the will to live......do what you can and then go over with the proper grout (using a proper grout tool or sponge.)
John

 

[melodymaker67]

You are joking !!! It took me ages to do that. Thanks anyway but gutted