Looking for a Top Off Tank

[layer3switchguy]

Hi folks,

I have a limited amount of cabinet space and need to find a slim container to hold 3 - 5 gallons of top off water and a Tunze Kalk Reactor. I also have the Tunze Osmolator.

Any advice on where I can find a slim (3-6" wide and roughly the same in depth).

Thanks!
L3