Adding a 2nd CO2 reactor

I currently have an Aqua Medic 500 reactor in 1 corner of my tank
driven by my Eheim 2217.
I'm losing some CO2 from the base of the reactor, so I'm going to add
a 2nd reactor which I'll put in the other corner to help with CO2
distribution.

I've ordered the Aqua Medic reactor 500M - same as the 500 but with
its own pump.

I'm hoping (!) that I can just cut the CO2 hose that comes from the
needle valve and insert a 2-gang adjustable air valve (the little
green plastic ones with screw tops, used with air pumps) so I can
split the CO2 between the reactors.
Is this method OK?

Thanks
Pete