Our kitchen floor was tiled only a year ago but the grouting is already foul. This is partly my fault I guess because I only mop about once a week but mostly I like to blame DH for putting the tiles too far apart and giving it a lumpy finish. 
I know I can go at it with a brush and clean it but it will look gross again in about 10 min.
Can I get someone to put new, darker grout on top or replace it completely? or will it have to be retiled?
Asking mumsnet before I ask a tiler to do this horrible job!