I'm draining my pool to get rid of 4 years of CYA (thanks to my pool guy) and CH buildup. I have a DE filter and I'm using the Waste option on the mulltiport valve. I closed off the skimmers so just the main drain is pulling in the water. What is weird to me is that my spa has slowly been draining as well. I have an actuator on my system that is set to pool. Also, my skimmers are empty now. I would have thought that once the water level dropped below the skimmers they would just sit with the water that was in them. Also, the little output things under the skimmer (we got the upgraded Paramount skimmer things) are dripping water. Do I have a back flow, or some other type of, problem?