I wouldnt even take the fish out of the tank, if you were gonna cycle with the fish, this will be WAY eaiser on them than going through a normal cycle. So just leave them in there, and add the correct amount of bio-spira and then keep an eye on your amonia and nitrItes, they should slowly start going down, and you will then see nitrAtes appear...voila you're now cycled! Bio-spira is also hard to get a hold of sometimes. If its not kept in a refrigerator, then its not the real deal so dont buy it.
If you cant get a hold of any bio-spira, try and get some filter floss from an established filter...ie: from the fish store, or perhaps someone you know with a tank thats allready been setup, ust put it in your filterI would do this on the 2.5 gallon as well. being that its such a small volume of water it will really help, because smaller amonts of water are more than likely going to be harder to keep "in check" they tend not to be as stable, imn regarrds to water chemistry.