Yesterday, I was testing my tank and my nitrates are off the chart. I went to get water and had my LFS test my water. I was sure my test kit must be off. No its high. Ammonia 0 Nitrites 0 Nitrates 160 pH 8.0 I have changed 40 gallons of water about 4 hours ago. Possible causes: Redid the aquascape. Can't find my serpent star in sump. Possible overfeeding. I have cut my feeding way back. How long should it take to fix this. My coral and fish are doing fine. I am waiting for a order of snails that I am putting on hold until I get this under control. Thanks for any help. I am very frustrated. I have a skimmer in my sump but it is down until Monday because my husband broke the venturi piece and we ordered it overnight.