ok, i am doing my own experiment. i purchased some play sand from K-mart. the package says fully rinsed and sterilized. it is a fine white sand. i have it in a 29 gallon tall tank, 5 pound piece of live rock and my 2 damsels. salinity is 1.022, temp 80, ph 8.3, ammonia 0, nitrites 0, nitrates...