Our builder started up our pool on Friday around noon and within 24 hours the travertine spillway from our raised spa into our pool is starting to erode away. The rocks are just dissolving. I checked the pH and it is 2.92. The builder said they added 10 gallons of acid to the pool. I think the pool is 17,000 gallons. They are coming back on Monday to neutralize the water. Looks like they are going to have to replace the travertine pavers on the spillway. Just curious if anyone else has run into this. The builder said they rarely have a problem with the travertine pavers but at this pH I would think it would be expected.