I have a Betta fish that I got in March 2007. I keep him in a half gallon tank and with some fake plants and he was really active and his color and size exploded (he was kind of sickly when I bought him). I decided that he was much too big for his bowl so I bought a 1.5 gallon tank from the pet store. It was only AFTER I bought that tank that I found this website and the consensus here seems to be that I need a 5 gallon tank minimum.
I know that since I've moved him from the .5 gallon bowl to the 1.5 gallon tank he's become much more active again. Do you think I should immediately upgrade to a five gallon tank or will this tank do me for a while? I think he's pretty big as far as Bettas go (he's about 2.5 inches). I'll include pics of the tank.