Got my first Betta from Petco About a week ago, He is in a Evolve 4 Gallon Tank, With a Aqueon 50 Watt Adjustable Heater temp sits nicely at 78, Is also equiped with a Filter, The First few days I had him there was a plastic plant that tore his fins and he developed cloud eye, he would not eat at all the first week, and sat near the top corner of the tank, however after doing a 100% water change and adding Prime, Aquarium Salt, and doing a half treatment of Betta Fix he is now full of energy and eats like a pig.
:) Let me know what you think.