I have a 72g tank that has been set up for over 3 months. My test readings are 0 amonnia, 0 nitrites, >5 nitrates 0 phos, cal 460, alk 10 dkh temp 79 degrees. I have a 150 gallon wet/dry with bio-balls replaced with live rock and 4 powerheads giving me around 20x turnover. I also have a...