My 3 year old Betta, Alpha, has been lying at the bottom of his bowl today. He sometimes would lay on his plant but would then swim around if I moved the bowl. Now if I move the bowl, he swims to the top for air, then goes back to lying down. He also isn't eating. I just changed his water- I used to use bottled water, but have been transitioning to tap water that I've let set out for a while, and have been using Betta water conditioner. Could his condition have to do with the new water, or is he just getting old? Thanks!