pool tile repair
 

tile in pool needs to be cleaned of mineral corrosion or replaced. Any recommendations of companies to do this?

Budbetty, something sounds very wrong. The water in your pool should not be so hard as to cause deposits to form, and certainly not acidic enough to damage the tiles. My I suggest, have one of the large pool companies (we use T&D pool and Spa) come out and look at your pool and specifically your water chemistry. You may need to have the chemistry adjusted, and a really good cleaning.
Hope this helps.