8 gallon

[chatterbox]

cause i dont wanna but this tank in 2 gallons 4 2o dollars.cause it looks terrible and looks cheap on the net

 

[SConrad]

i have that tank above...its pretty good and my betta loves it...

u can also go to walmart and get a 1 gallon tank for 10$ with an air pump and light

 

[GuppyDude]

i dunno they all look like they will work, but a couple dont have lids on them. bettas love jumping ( a lid is a must )