Its the nitrogen cycle. It doesn't start until there is a source of ammonia. This is where fish come in or you could cycle fishless, but then you still need to provide a source of ammonia. The fishless way is safer to the fish and you don't need to do water changes to get your levels down if you don't have fish to worry about. Any additive you place in the tank will not matter if there is no ammonia for the bacteria to feed on. This also includes the gravel from your other tank. The good bacteria will start to die off if there is no ammnia to feed off of.

There are a couple of threads that have been recently started by a few of us that cycled our tanks fishless.

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Enter your tank into the tank of the month competiton
http://www.aquariumforum.com/f2/febr...ion-27354.html