I use currently the BM mini Q and it works amazingly well. Such a small footprint and really nice quality feel to it versus some of those others on the market. Generally as long as you rinse it out really well and set it just above the water line that's marked on the body of the skimmer.
Power it on and dial in the water flow so that it is just at the very bottom of the neck of the skimmer chimney and keep an eye on it and within a few hours you should probably start seeing some skin working its way up the chimney. It will export some micro bubbles into the tank for the first couple days but as you dial in the flow and maintain the correct water height within the tank the micro bubbles will go away.
Another plus to the skimmer is it is dead silent!
