Okay just got my IN-250. Set it up yesterday in a separate tub to break in before putting it in my sump. I know it says to put it in 6"-8" of water, but what is everyones experience with this? It's been running since yesterday after noon, and the bubbles haven't started going up the column. I do have it all the way open, so probably have to close it some. How long does it take to break in? I have to say so far this thing is silent. When i first turned the pump on, i expected to hear it making some noise, but nothing. So far a great skimmer, can't wait to see this thing in action on my tanks. I have a 40G breeder and a 75G plumed togeather on a 40G breeder sump. For a total of about 150G of water, and plan on adding a frag tank to this setup later.