Hi all. We were gone for the weekend and I came back to a green pool. I had someone turn on the filter for a couple hours everyday but unfortunately I did not check the chlorinator before I left. When I checked today, it was empty. The pool was crystal clear blue before I left on Friday. The pool has brand new water from a month ago. What's the best way for me to get water nice again? There's no algae, just green. I put in two bags of shock I had left from before and the floor of the pool immediately turned blue so I'm sure it's just a lack of chlorine. Should I put in liquid chlorine? Thanks in advance.