I just set up another 120g tank with a sump filter. Im filtering about 1400gph right now. I put previously used filter media in the sump and a large piece of drift wood from my tank (1 year running it myself, and a friend ran it for a year with the same wood too) into the big tank. This has been running for 7 days now, and according to my tests there are no nitrites, and 0ppm ammonia ... Is it possible this tank cycled in a week!?