I just put one of these in my tank and I am not sure if its hooked up right. The nozzle coming out of the maxi jet 1200 pump is pulsing. SO far its been in 4 hours and I dont see foam but I understand I have to wait a while. How do I know if everything is working right? Its pulsing and throwing out bubbles.\r\n\r\nTheres a knob on the inside, is that to adjust? I don't know much, but I have a feeling something isn't right.