Phosban reactor as zeovit reactor

[hecks220]

Anybody have any ideas how i can keep my diy zeovit reactor which is a phosban reactor from getting air around the zeolites when i shake it. Currently i disconnect the hoses, pull it out of the sump, plug the holes and shake it. Some air bubbles get around the zeolites harming some of the micro-organisms...does this sound right? Any thoughts would be greatly appreciated! Thanks