Quote Originally Posted by poolaris View Post
I was going to drain my spa water into the pool, . . . . Just to be on the safe side I poured 8 oz bleach which raised CL to 16 but also produced a CC of around 12.
Most likely this result could mean you've used the spa quite a bit, and haven't drained it recently. It could also be weird pool / spa chemicals have been used on the spa.

Have you been using any non-BBB chemicals on the spa? Do you cover your spa?

If you want to find out WHY the spa is like that, hang on to the water for a while. Otherwise dump it -- not into the pool! -- and refill.