Hello, I have a Neptune Apex A2 but I have just filled my last aquabus port on my controller and EB832. Can the extra aquabus port on the Neptune DŌS or Neptune AFS (feeder) be used to connect additional equipment? Is it possible to daisy chain an Apex PMK Par meter through the extra port on the DŌS or AFS? If not, what is the exact purpose of the extra aquabus ports on the DŌS or AFS?