The betta seems to have gotten comfortable with it. He found his way to the new tank within about 10 minutes, and stayed there most of the day, then went back to the old tank (maybe because the plant he likes to sleep in is there). Now he somewhat frequently moves back and forth though he seems to like the old tank a little more (maybe because the new tank is empty). I want to put a thing or two in there but do not want to crowd it and the other tank is pretty crowded. I would like him to keep the swimming around room.