well I have had the skimmer up and running for 2 weeks now and love it My nitrates are still in the too high for me range....but on the down side my sump cracked last night and dumpped about 3 gal of water in my dinning rm and basement before i caught it...so i am in the process of rebuilding and yes the skimmer was n the 1st section of the sump and kept a fairly consistant water level.