Designing Kitchens and Bathrooms - pre mix grout problems

I've removed the grout around the ceramic tiles in the shower where necessary. Not a really big area. Got some pre mixed grout I followed all the directions including stirring thoroughly. It did not work. It is sandy/gritty. (This is not a sand grout). I was told it did not have enough water so I tried adding a little water. Still does not work. Should I just take it back and get the kind I mix myself. Do I need to buy a mixer even though I am only using a small amount? Many of the threads say to add something to the grout. Is this necessary?

Since you only have 3 previous posts, I won't beat you for not listening to many of us. "Don't use premixed grout", it is a waste of time and money, fortunately, not much money. What do you call sandy/gritty?? Sanded grout has sand about the size of beach sand, fairly course, and is needed for joints larger than 1/8". Unsanded grout usually feels almost grit free( and is fairly easy to work into small grout joints), but all grout needs a binder, it is the size of the binder that differs. If it is not working for you, stop before you make things worse. Adding water to grout to thin it will often weaken the finished product. The grout should be about the consistency of peanut butter, to thin is no good, to thick and you may not get to the bottom of the joint.

Throw that stuff away and get some real grout. That premixed grout has been nothing but trouble, I can't understand how it can still be on the market.:)

I've removed the grout around the ceramic tiles in the shower where necessary. Not a really big area. Got some pre mixed grout I followed all the directions including stirring thoroughly. It did not work. It is sandy/gritty. (This is not a sand grout). I was told it did not have enough water so I tried adding a little water. Still does not work. Should I just take it back and get the kind I mix myself. Do I need to buy a mixer even though I am only using a small amount? Many of the threads say to add something to the grout. Is this necessary?

You are all right. I took it back and spent much less on a small container of plain grout. It worked like a charm. I'm misting it and waiting for it to dry. Then I will seal it. Thanks.