How often should I change the water in a 1.5 gallon tank?

[Alienbetta1]

Ahh so if I got a ten gallon how often would I have to change the water?

[BettaxFishxCrazy]

You'd have to cycle it (which I know nothing about.lol) but you would never have to do 100% water changes on it. I think 50% weekly? And you'd have to get a syphone(sp?) to clean the bottom of the tank, but I don't think they're that expensive.