Moumda - I prefer to leave the pump at full blast unless you can't keep the water level below the top of the skimmer box and adjust the air valve to control the skimmate thickness. With the AquaC skimmers, the more flow through the injector, the more air that gets sucked into the skimmer body. By cutting back the flow and leaving the air valve wide open, you won't get any more air than leaving the valve wide open and restricting the flow.
TheMorayMan - Unless your pump is too powerfull that you can't keep the water level below the top of the skimmer box, I don't see any reason why it would be beneficial to take it off.