To answer your question, you are going to need a chiller, though they are expensive (many time more so than a heater). I really don't think a fridge would work.
I have heard of people making homemade chillers using mini fridges and copper piping.
However, since you have to ask about this, I think it is safe to assume you are in over your head and do not know how to properly care for these fish.
Now we just wait for the update that they died, or he let them go. *sigh*
Heat is a major issue for me also. I keep a Goonch and it likes cold, fast moving water. I removed the lid of the tank and keep as much water flow at the surface as possible. Just point the return lines to the surface to make surface agitation. I also use a fan to push air across the surface of the aquarium. My house temp is at 80 and I'm able to keep the Goonch tank at 74. I never turn the light on, it's not even on the tank anymore because I removed the lid. Good luck!
These are the kind of answers i wanted not a bunch of whiners telling me how cruel it is to take two of fish fry out of a lake with thousands of fish. Thanks for being resourceful to those that gave me helpfull responses quickly. You made the fishs' short stay a lot better.