There have been many discussions regarding Baqua Spa, both positive and negative. May I suggest that you do a search of previous threads regarding Baqua Spa over the last 6-12 months, enter key words Baqua-Spa.
Some people love it, and some people hate it. It is a subject that is full of controversy. The biggest one being, you can only use baqua spa products in the water, absolutely no other chemicals.
Do you have ozone on your Hot Tub? If not, I would suggest starting there. But then, you have already switched to Baqua.