All great advice above. I highly recommend sponge filters for small tanks. Less current, more area for the bacteria to colonize, quieter when you use one airpump for several filters.
If you're cycling several small tanks simultaneously, use fresh
Tetra Safestart. Dr Tim's One-and_Only, available online, ships from the factory in an insulated container, to guarantee freshness. Other good cycle starters are API Quickstart, ATM Colony, Niteout and Stability.
Remember: Cycling is not for the convenience of the keeper, but for the health and safety of the fish.