Hi kmac,

If it says your salt level is okay, then the first two things I would do are: 1)test the water for FC right where it's coming out of the unit (there should be SOME chlorine in that), and 2) turn off the SWCG, Add enough bleach (liquid shock) to get your pool to a known level of chlorine at night, test it for chlorine after sundown, and then test it again in the morning before the sun hits the pool. If you've lost more than 1 ppm of chlorine in that time, then your chlorine is being used up too quickly fighting something in the water and you need to shock it.

What is the CYA level in your pool, and have you checked the manual for this new unit to see what level it requires?

Welcome to the forum!!