you could DIY.. with a 5 gallon bucket from home depot or a old bucket of salt.. Alternatively you could do a petco special 5.5 gallon for $15 and cut a piece of plexi for a top... could even spray paint the outside
I have this slim 10 gallon that I bought to downgrade from my 20 gallon one. I'm probably going to go back to the 20 so I don't have to refill so often.