Hi folks,

Forgive my ignorance, but I am attempting to replace some of the tile grout in my shower for the first time. Have come to this forum for most of my home improvement advice, hopefully you guys can steer me in the right direction....

The grout in need of replacement is where the tile meets the shower basin (see photos). The original shower had what looked like standard grout (similiar in appearance to the other tile grout throughout the shower) but has recently discolored and is beginning to decompose. This grout is approximately 1/2 inch wide in places, and under steady water exposure.

My questions are:
Several friends have suggested using chaulking - is this an option for this application?
Is it best to replace existing grout with regular sanded or an epoxy grout?
Is it best to avoid pre-mixed grout?

Any other suggestions or advice would be immensely appreciated! As always, thanks in advance!