A couple of years ago, we purchased an Elite Platinum II Spa. It has always had air flow problems. Usually, I fix the problem by unplugging the power source, washing out the filters and restarting. Now, I continue to get the --LF error message. The spa seems to be working fine... other than that. The spa will not heat since the low flow problem shuts off the heating element. I have noticed that for the past year or so the bubbles flowing out of the ozonator inside the spa have been severely decreased. About three months ago, I replaced the LCD electronic board. I see my options as the following: 1) empty the spa of water and refill, 2) replace the circulation pump, or 3) somehow identify and fix the air flow problem. I am having trouble identifying the circulation pump to inspect. Any help would be greatly appreciated!