I have the same issue poor decision not forcing the pool builder to use silicone grout.
Calcium buildup on tile grout.
The soap is used to thicken the vinegar creating a heavy coat but it takes time for the vinegar to work thru the layers of built up.
Let the tile dry completely.
Showers can quickly turn grimy with mold mildew soap scum and hard water deposits.
Try mixing half white vinegar with half dishwashing soap in a spray bottle.
Calcium bicarbonate commonly known as baking soda is also a chemical composition that has deep cleaning properties.
The glass beads are under air pressure and they literally blast off the calcium and leave the tile untouched.
Apply a coat of it on the affected floor with the help of a toothbrush and rub it in gently.
Because the grout joint is commonly lower and more porous than the tile the dirt tends to be observed in the grout joint.
Ok so not so much on the tile but on the grout.
Scrub the tile with a scrubbing brush or pad to remove the next layer of calcium buildup.
A common problem in many homes hard water contains a high amount of minerals such as calcium that will quickly begin to build up on shower tiles.
Preferably the dirty water should be vacuumed off the floor.
If you have hard water you have probably already discovered that calcium deposits build up quickly if untreated and can be difficult to clean.
It is not pure calcium carbonate as ma would readily consume it.
In severe cases the dirt will also discolor the tile.
The pool water is wicked up the grout.
Leave on tile 2 to 4 hours then scrub and rinse with a brush.
These deposits will cause shower tiles to appear dull and dingy.
There is no mistaking the ugly build up of calcium deposits on tile.
Normal cleaners do little to dissolve the calcium deposits and all purpose cleaners do not even scratch the surface of the hard water stains.
Step 4 scrub and scour because calcium buildup is adamant and hard it will not be possible to simply wipe it clean with a mop.
That is evaporite scale.
The only way to clean off the calcium deposits is to hire a company that does glass bead blasting.
A couple of years ago i was quoted 3 00 a linear foot for cleaning.
Because calcium deposits add up layer by layer you ll need to remove each layer until you remove all the buildup.
Don t be fooled into thinking you need to buy expensive commercial products to clean your tiles.
You can then apply a sealer to safeguard against future calcium buildup.