My best approach is get a small powerhead for the opposite side of your tank. If you still want to treat it with cipro, then the 10g hospital tank will do just fine, just be careful not to damage the foot of the nem. Keep an outstanding eye on your parameters. If that peppermint died and you didnt find it, that is enough material to spike the ammonia an nuke your entire tank because of the low water volume, It really doesnt take much to taint the water in a tank that small so it will be crucial to keep an eye on the params for the entirety of the 10g tank.