Unfortunately, stomach acid is actually necessary for the digestion and absorption of Calcium (as well as other nutrients) and as an ANTACID, Tums actually creates the opposite environment. I actually recommend that for increased absorption, Calcium supplements be taken with something acidic like orange or cranberry juice.
The better option is to determine where your indigestion is coming from and address those issues... Your body may actually be deficient in Hydrochloric Acid so it overproduces to compensate when you eat, or you could have a hiatal hernia, where the stomach has herniated above the diaphragm, causing stomach acid to leak into the esophagus and throat. (This can be fixed by a simple, effective adjustment and I have seen many patients successfully eliminate long-term antacid use from their life thanks to this adjustment.)
If you or someone you love is suffering from indigestion, feel free to share this post with them!
Stay healthy!! :)