I moved my tank not last weekend but the weekend before. I took everything out of the tank and laid it out on some clean towels. Drained the pumps and also laid them on the towels. Caught the fish, put them in a treated holding container until it was time to move them back and drained the water in the tank down to about 2 inches. Then I had my husband help me carry the tank into the new spot in my office. I then reversed the process and put the fish back into the tank. I did not clean anything at all other than the water in the tank. The next morning I got up and tested the water and sure enough the move sent the tank into a mini cycle. The fish are fine, and I am waiting out the mini cycle, but what could have caused it? I was very careful when I moved everything.