is there anything to put in my 2.5 gal for my betta to play with or help him get some exercise? i saw this mirror by zoomed and thought if it would be a good idea or any other that could be fun for my betta.
I use that mirror and I really like it. Just make sure its not stressing out your fish and you should be fine. I usually put mine in the tank for 5-10 minutes depending on the fish.
If your fish swims away from it and hides don't continue to put it in there because it will just stress the fish out. As long as the fish is flaring and displaying its fine. If the fish attacks the mirror take it out because it will stress him out.
You can try putting a ping pong ball in there.. my fish always ignored it though. I wouldn't worry too much about exercising your fish unless it looks like its getting too fat.. even then lowering the amount of food should keep it in form.
Yeah you can do hamster tubes, but like xxabc said, they can't be too long. You could also put in a glass coffee mug or buy terracotta pots at a thrift store for cheap and smash a couple pieces off so your fish can go in and out of it (make sure you sand down the edges so they aren't sharp). Some people put little balls in there that float on the top and it keeps them entertained. You can also draw on the tank with washable markers (some people use this method if their fish are biting their tails because it helps distract them).