Is it ok to move fish around within the same tank? I have 4 fish in a 20 gal and rather than moving their decor around, I was wondering if it's ok to change which section they are in? This way they can get a different view and change of surroundings.
what about changing fish around from various tanks? is this ok or would it be too stressful?
I would just change the decorations a little. It all depends on how stressed your fish get. I know my male betta gets terrified as soon as I even put my hand in his tank to fix something. My female betta on the other hand could care less if you took her out of her tank, and plop her into another. All of my other fish are afraid to go into the large container I put them in when I move them, but once the get a second or two to relax they are ok.
I did this a few times with my divided 10 but really its just better to move their decorations. Bettas set up territories and to be taken out and plopped into a new space thats not "home" is probably more stressful than good.