Hi!! First time closing a SWP. Pool has been great, crystal clear all season. It s an 18X33 above ground. I will be using the return jet plug as well as the skimmer cover door with gasket that tightens from inside the skimmer. Pump, filter and all plumbing will come inside the house. (Union joints are great). I have (2) 4x15 pillows to go lengthwise under the cover. Chemical readings are good. I purchased 2 of the slow release chlorine canisters to hang from the pillows during the winter. Any other chemicals to add before putting the cover on? Thanks in advance.