1 gallon tanks should be cleaned every other day, half gallons are just unsafe period. He's more then likely going to be stressed out yes, but it's healther for him to be stressed then to be sitting in his own ammonia filled tank.
If you kept his cup he came in you should be able to just scoop him out with that whenever you go to change his water. You can trick him into thinking he's going to eat so that he's up at the surface of the tank and you just scoop him up with the cup. It's less stressful and less dangerous then using a net.
Using API Stress Coat+ as the water conditioner will also help him be less stressed out during water changes. If you're thinking he's going to be in that little tank for more then a week you might be better off going to walmart and getting him a 1 gallon diamond tank. Those tanks are $10 where for the same thing at PetCo it's $15. If it's unfiltered you should be changing the water every other day, if its got a filter then once a week do a 100% change.
Last edited by TheCheese909; 08-16-2012 at 10:05 PM.