I have an RL150 and notice this when the skimmer has been off for a while.. I usually open up the valve on the skimmer and let it do its thing.. Is it producing lots of skimmate? also is there a kink in the air tube because that will cause extra bubble production.. Let me know if there is anything else I can do to help..
Does your skimmer self start every time.. I have to blow in my air tube every time I restart it.. What a pain!!!