<a href=showthread.php?s=&postid=13924999#post13924999 target=_blank>Originally posted</a> by Pike614  
OK, so I am getting the skimmer dialed in...the tank ios 2 months old, and the skimmer has been on since.  I loaded my 450 with about 500lbs of dry pukani rock, another 350lbs LR in the sump..and am now feeding the Reeflo 250 with a Quiet One 3000.  My issue is that I am seeing my nitrates creep higher every day!  I am at about 80 for nitrates now, with only 5 tangs and a bunch of smaller fish.  My thought was that spending more on a nice skimmer would mean no nitrate issues.....but here I am again seeing nitrates on the rise.
My question is: does the skimming performance differ when using a feed pump from the sump vs. fresh "dirty"
 water from the overflows?  Or are the nitrates a result of the dry base rock curing and becoming live?  If so, wouldn't I have seen this earlier on?  Any info will help!