Pedal noise and power supply

My demon fx 66 came in today and it's really good except that I don't have the right dial for my amp in the moment ( I'm not good with dialing in tones ). But I can't push the pedal more than 50 percent and even reducing gain wouldn't help at all. Any advice except a noise gate? ( I'm gonna get one in a few weeks but need a quick solution )

And the other question is if I can just turn the pedal off but still connected to power or if it may cause damage over time being under constant electricity.