i have a 3" senny in a ten gallon and i just bought a second one today. he/she is about the same size just a little smaller, an inch at the most. id like to put them both in the same tank to grow them out. is there anything i should know about how to do this or should i just stick the second one in there and he'll be fine. should i rearrange the decorations a bit to disrupt any territory lines the other one might have? haw about a water change?