We just reopened our lap pool after being shut down for a full 5 weeks. Once the contractors who were doing renovations to the roof got out, the pool had 0 chlorine and pH was low, 6.9. The filters ran intermittently during this shut down, but the pools remained filled. When we first got everything back up and running, I was looking at a slightly cloudy pool. After a couple days I had the chlorine up (~3.5) and the pH was slowly rising. We added clarifier and the cloudiness went away over the weekend before opening. We've now been open for a week and the pH is up to a 7.3/7.4 and chlorine is maintaining ~3.5 but my water has taken on a green-blue tint. Alkalinity is 70 and Calcium Hardness is 325 as of this morning. The only thing that is different from before the shutdown is that we have a new heater system. My only thought is that maybe the low initial ph was corrosive to copper in the new heating system and that has led to the color change. I'm thinking we should add a chelating agent to clear it up but wanted to get some input before I go and spend the money. The pool is 100,000 gallons.