BlueCrayfish.com

I would suggest a really cheap filter like one of these [img]https://encrypted-tbn2.gstatic.com/images?q=tbn:ANd9GcQscDHGtXnsJ4fRMD3Two5yPsWblg7ZMAwMRVcRFMtWeyp82ckq[/img] [url]http://ftffacoop.com/index.php?main_page=product_info&products_id=843[/url] I have never used the website that sells this filter before though, I am use that you can find these on ebay or at a local pet store

No that will probably not be enough. The beneficial bacteria don't really live in the water so much as on the surfaces of objects like the gravel substrate.

I would highly encourage you to get a filter, even if it's just a cheap one from wal mart or whatever. The way you can quickly cycle this new 5 gallon tank is just put some gravel from the established tank in there.