Mobile chiller setup?

[miksha_]

Hey guys I'm teaching a class and we need a few animal kept in cold water such as starfish....we have a 20g that had a chiller set up but it's broken for the time being. Is there any way I can set up a 5 or 10 gallon in my classroom with a starfish, and somehow keep the water cold for a few days? Thanks!

 

[Fat Homer]

Off the top of my head i can only think of keeping the ambient room temp cool enough to keep the tanks temps down...

Frozen ice bottles might work as a temporary option but need to be constantly replaced throughout the day, so probably not going to work if the tanks in a classroom...