I would keep an eye on your parameters and wait a couple of days to let the bacteria adjust. If your other tank was running empty, then it would not have been cycled because the bacteria need ammonia to survive and there was nothing in there to create ammonia. Essentially you are doing a fishy cycle on the tank right now, so keep up with your water changes and keep an eye on everything.
If you measure the tank, there is a link at the top of the forum that says "Conversions" where you can put the dimensions in and it will tell you what size tank you have. If it is actually a 5.5 like I am suspecting, then I would not stock too many more fish, as there will be babies to account for also.
Kristina
