This morning my friend said she had a gift for me, so she shows up with a preowned 20gal fish tank with fish in a bag. The tank was emptied and all the parts bagged up. I don't know how to start this process at all! I have the used filter that I making sure to keep damp but other than that... I don't want to fill the tank and plop the fish in but then again they probably aren't enjoying the bag. Any help would be appreciated!