I've cleaners, polishers and sealers. Nothing seems to work to rid top of water stains.
Here's a link on water stains and how to remove them:
William: Sorry you. have this issue. ...maybe these ideas will help:
If you are not using marble cleaner, mix a squirt of gentle, non-abrasive dish soap with warm water in a spray bottle and spray the counter generously. Scrub gently and wipe soapy solution off with a clean wet cloth. Repeat process until all soapy residue is gone. Rub the countertop dry, and buff with a soft absorbent towel.
The Marble Institute of America, or MIA, advises against using vinegar, lemon juice or other cleaners containing acid on marble, including bleach as those products will etch the marble.
Marble is basically compressed limestone. Any acidic cleaners will etch, dull and stain the surface, including vinegar, citrus cleaners, lime/calcium cleaners, and bleach. Marble countertops also don’t like it when you use something like Windex on them because it strips the “seal” off of the stone.
Clean and brighten your grout with this easy homemade grout cleaner. Simply mix baking soda and hydrogen peroxide into a runny paste and scrub with a toothbrush. Let the mixture sit for a few minutes and then rinse it off.
If you are trying to remove an old stain, create a dense paste of more baking soda and less water. Then place the paste over the stain, allowing it to function for a few minutes. After that wipe off the baking soda paste. If it is needed you can repeat the procedure until the stain vanishes.
If the stain is persistent and is still there you can try removing it with ammonia solution. Make the area of the stain damp with 10% ammonia, diluted in water. Ammonia is knows as a base solution, so it is suitable for removing stains from marble.
The final stage of the stain removal us rinsing. Rinse the solution from your marble well to eliminate any residue, left from the cleaning ingredients on it.
I advise to use gloves when removing the stain with ammonia. They will protect your hands. Ventilate the room, in which you use ammonia for removing stains, because it is toxic.
I found an quick idea for you to try
Just from my own experience, I only use a marble cleaner and sealer made by Weiman. I use a damp microfiber cloth to wipe it in between. Use coasters to protect the surface. Most cleaners you could use on other surface may damage your finish. If the water you accidentally get on it doesn't bead up, you don't have a good seal on it. Marble requires some care, but, after a year+ of having it, I just do a thorough cleaning with the purchased cleaner once a week. I spray the sealer on the cleaned surface when it is dry, buff it in, whenever I notice water not beading. Because I use my counters daily, and it wraps around my sink, I seal it about once a month. So far it is still as beautiful as the day it was put in. Good luck!
There are lots of ideas here:
Here's some good tips
Once a year any granit marble any pours material you need to seal so that won’t happen you might need to get a professional to come out to polish it and seal it.