Sure. Depends on dimensions and all, but it would sure be a sweet shrimp tank.
Depending on the person, dimensions and filtration, someone might recommend ONE dwarf puffer.
It would be a cool neocardinia tank with least killifish (7th smallest fish in the world, see my 18" signature)
And you could always just focus on plants or snails.
MABJ's iDevice used for this message :p
I have tried shrimp before but not much success any suggestions on plants? i have a mirimo ball, wisteria, some dwarf hair grass (like maybe a square inch) in there now but not sure what will be best
Filter is an air driven cheap one rated for up to 5 gallons
I would love to get a dwarf puffer but no idea how it would work out