is a grouting pen any good? i saw one in b n q today but was unsure. it said on it that if you went too far over the line you were filling, that you had to wipe it. i would be scared to do that in case i touched the line and it smudged. it also said you had to get a good flow on the pen so i would be afraid to run it along and not get a consistent line where needed.
Bought one after seeing the demo on Shopping tv, which gave a tip and a roller application. Was simple to use but hopeless as a finish, remember walls are not lying flat and all existing gouting is not perfect. Finished up in the wheelie long before all used up.
Waste of money: the nibs/tips usually wear away long before the liquid does so you have to get a small brush in there to finish the job. Better to rake out the old stuff by a couple of mms and regrout...
I've just finished whitening my bathroom tiles grout with Cillit Bang with bleach. All you do is spray it on and the foam expands, wipe over it lightly with a sponge and leave it for 5 mins and shower spray it off. Zing!!
If you just want to whiten existing grouting try having a scrub with a toothbrush dipped in a bit of diluted bleach. It really can make a big difference. Just rinse it afterwards. I did try a grouting pen once and wasn't impressed - quite hard to use.