my 30 gallon is just about cycled with 15lbs. live rock and aragonite sand, 0.0 ammonia, 0.3 nitrite, lots of nitrate, around 50, temp. 78, pH 8.2, SP 1.025, alk 70ppm and calcium 360ppm. I am going to do a water change once my nitrites go down to 0. My sand is completely covered with brown algae, is this normal for cycling, and will it go away on its own, or do I have to clean it somehow? Also, two of my live rocks turned partially white and covered with brown algae, all my others look healthy (I bought cured live rock from the tanks at the pet store), the two that turned white with brown algae are quite close to one of my powerheads, could this be the reason why only these two did that? too much waterflow around them? thanks to everyone for responding to my questions lately, you've been great help.