I whacked my feeders before, now that I am starting over, What is the best method, when I get up to big rats I think I would put a hole in the wall whacking LOL! I don't think CO2 is really an option for me, I don't think it is worht the time and effort to go searching and have it not be available when I needed it. Also I have heard of people suffocating the rats, is that a risk, I know it is a bit inhumane, but so is feeding live and people do that. I will probably continue whacking, but just trying to see the best way. Also I found an instant killer by accident, my brother wanted to see my ball eat live, so we decided to do it without risk of injuring the snake, we triey to tie the mouses mouth shut with thread, as soon as the thredd was tight, we coulden't even tie a good not, the mouse was dead! the thread was loose so we slipped it off! instand dead mouse!