My first (maybe curbless) Kerdi shower

[dappelha]

I ripped up a 2x3 section of ditra and spent half the day grinding back to the subfloor. Found a 60 grit flapdisc and angle grinder to work best but incredibly dusty. New ditra is down and floor is flat now though.

I've put up the kerdi on the walls and banded all the floor seams and up the wall a couple inches. I overlapped the kerdi membrane itself on the walls and into the pan instead of using kerdiband. Took some more effort to get everything tucked tight into the corners and all the bubbles out, but it looks good now and one less seam and build up.

[dappelha]

All the tile is on the floor and walls and now I'm getting ready to grout. The back wall is polished marble, 1/16 grout lines and the white hexes are porcelain. Advice on previous threads seems to be mixed on whether I should seal the marble and if I need a grout release on the marble (Davey says sealing is a waste of time).

Opinions? Should I use a 511 solvent based sealer on the marble before grouting? I was thinking of using either CBP polyblend unsanded or trying something new like fusion pro or flex CQ. Any cautions on using non-cementitious grouts on marble?

Thanks in advance! The bathroom is coming along great thanks to the help in this thread.