Caulking this connection is fine if the wall is some sort of one piece sheet or enclosure but with tile it should not be there.
Grout between tile and tub.
Spread the material in sweeping arcs pressing it into the joints to fill them completely.
This might include any grout along shelves corners and floor tiles or the grout and tile that surrounds the shower drain.
As with any other gap near your bathtub you ll want to close the opening to prevent any possible water damage or the onset of mold and mildew.
Use a hard edged rubber grout float and hold it at a 45 degree angle.
Then grab that stiff brush again and give it another scrub.
Pour a quart to half gallon of grout on the tiles.
This gap may widen over time as your home shifts.
As commonplace as it may be as seemingly logical as it may be it is still wrong in many cases to caulk between the tile and the tub.
Similar to the gap that can exist between your wall tile and tub you may have a space between the floor and your bathtub.
The sole purpose of grout is to fill the spaces between tiles after the tiles have been glued in place on a floor or on a wall.
Grout fills the joints between tiles.
If the tub tile connection is caulked the water cannot wick out through the bottom grout joint and moisture builds up and is able to feed the mold that eventually develops.
Grout or caulk between floor tile and tub.
The grout joints are designed to prevent water from penetrating the wall but any small amount that does penetrate is able to evaporate out and or weep out along the bottom.
Next rinse the area thoroughly and use a cloth to wipe the surfaces clean.
A magic eraser can also make quick work of stubborn stains but know that you might go through more than one to get a room full of tiles sparkly.
Work in a small area at a time roughly a 3 x 3 foot section.
Grout keeps the tiles from.
Allow the paste to set for a few minutes to work its magic and then give the grout lines one more agitating scrub for good measure.
Gaps up to 1 4 inch fill gaps up to 1 4 inch in width with caulk.