Welcome to our forum.
Question for all the Hotspring dealers that replied. Can the customer add the Ace after the fact if they decide to? Or does it have to be factory installed at the time of purchase? If it can, if the customer isn't 100% sure, maybe they could try it out without the Ace to see, and then always add it later if still desired.
So theoretically you could really install it on any spa for the most part with a circ pump?