We moved into our house 5 weeks ago to a sparkling pool. Within 4 days of moving in we had a swamp! After multiple trips to Leslie's pool supply, a regimen to clean it, new filters, new filter manifold and o rings and lots of chemical balancing it's been fine but we noticed some small spots that we didn't think were there when we bought the house. And now they are going crazy and it's etching all over? I've tried researching on the internet and everything says your water chemistry is off but we've been testing it daily to make sure it's not. It did have some hairline cracks in it and it's on our list to resurface with Pebble tech in the next few months but any ideas what would cause this and how we can stop it or avoid more in the future?