http://www.fishlore.com/NitrogenCycle.htm - check this document, especially the fishless cycle part. "feeding" a fishless tank is pretty much taking the role of the fish giving off waste (ie: ammonia). rotting flakes or pure ammonia drops every 12 hours is good.
how are you adding good bacteria? when we started out, we bought a product called 'cycle' and it actually had a negative effect on our fish tanks cycling. BioSpira and Zymbac FW are the only store products i know of that are any good. You can also get good bacteria from some substrata or piece of the filter sponge out of a cycled tank.