I think your idea of running it off the CO2
reactor is a good one, then, and I doubt it will significantly impair your CO2
dissolution, since you don't really need a whole lot of power to achieve that, IMO
. I'm interested to see if you measure a difference, though.
I do believe those sterilizers are designed to have a Rio placed directly on that fitting, but since you'll have it running all the time it is more efficient to use the Mag you already have.