5 Gallon Stocking Help

[Tolan]

I have a 15 gallon I'm thinking of turning into a paludarium for some Spring Peepers since they're native to near me so I could catch them for free.
It'd be a 1/2 water, 1/2 land tank, so probably about 5 gallons of water. The tank would be at room temperature since it's ideal for the peepers. That being said I'd like to not have to use a heater.
What I need help with is deciding what fish could live in such a small amount of water, and could live in room temperature water.


Thanks for any and all help!

 

[Tolan]

Anyone? ._.

 

[Tolan]

Anyone? ._.

 

[creeker]

How about some Gambusia (mosquito fish.) You could probably find some in a nearby pond or drainage ditch. They aren't the prettiest fish around. They look like a female guppy without any color in the tail, but they are practically indestructible. They would be fine in the conditions you describe.