How do I clean old water marks on a glass table?

If the glass is etched you cannot remove the water marks. Best thing to do, is clean it up outside really well with hose and a cleaner degreaser. When dry, apply etching cream, you can get it at Hobby Lobby or Michaels and re-etch the top.

As Dee said re: etching. However if it's just dirt I would first hose off then spray with a foaming glass cleaner and wipe off. Once that's done, clean with microfiber and water to get rid of streaks.

I agree with Dee: You will never get it perfectly clean.

Water is a weak acid. It will etch glass, given time.

You can do many artsy things with stencils, wood and glass etch cream/liquid/fluid.

It is a weak acid, stronger than water. You need gloves and eyewear.

You may also want to get some: 'Frost in a Can' from the folks at Rust-o-leum.

So, think about a design you can live with, and remember: a Paint by Numbers kit can also use as an Etch by Numbers if you slightly dilute the Acid 25 to 36 different ways.

Try a cloth or paper towel saturated with denture cleaner & let it sit on the old water marks - might help!

Ammonia and water or Windex. Just let the liquid dissolve the worst spots before wiping dry.

Another little hint. A universal stone should be a pumice stone. You can use it on easily scratched surfaces like ceramic and glass. The stone is soluble enough that it would be like the Magic Erasers or a chunk of baking soda. Again, start gently, and if that doesn’t remove the water stains, get harder with your cleaning. If that doesn’t work, plan on etching, stenciling, painting, or choose a tablecloth. Again, best wishes!