When I moved something got into the water I never figured it out. I kept doing water changes etc. testing the water everything seemed normal but all my lps and colts died one after another. It devistated me I had this tank rolling for 4 years without much problem. I should also mention I was doing a lot of travel with my work and I'm sure that didn't help. Now I don't have the time, energy, or money to start over. The rocks are still in a tank with a protean skimmer and 1 pajama cardnal.