Reef Builders - The Source for Reef Keeping Information

i have had trouble with my nitrates now for about a mounth and half. ive put a reactor with nitrate away media, ive used carbon, ive changed my water every two weeks (40gal), ive got a refigum set up in my sump, dont know what else to do. the tank is a 180 gal reef no coral yet i have about 170pounds of live rock and about 3 to 4 inches of live sand tank has been going for about 4 mounths. i have five fish and only feed them once a day one pinch of dry food. (ph 8.2, alk 9,cal 450, phos 0, n02...