So I went out to check my levels and darn near zero reading on chlorine. Though maybe my reagent was bad so I took a sample to the pool store and same result. I cleaned my SWG a couple weeks ago and it looked fine. Salt level is 3300 and one of my returns spits out little bubbles when the SWG is "on" (tested this theory by turning it off and the bubbles stop). Don't the bubbles mean it's working? Any other way to test it? Thanks!!