I am a brand new pool owner. I just purchased a 19 year old house with a 20,000 gallon gunite pool with a spa that is located next to the pool, and appears to have a pass-through connection between the two. I have been checking the two pool skimmers, but since the heater has been broken, we have not used the spa. Yesterday I noticed that the spa had a skimmer cover (spa has been covered the two weeks I have owned the house), and I opened it to clean it out and discovered that it is not sucking. Admittedly, I am no expert with valves, etc, but when I check the spa valves, they appear to be all the way open for the skimmer and almost all the way open for the floor drain. Could the skimmer line be clogged in some way, or are there other valves that I may be missing?