Probably a good while. I have gone to Chattanooga which is a 9 hour drive from my house and got fish to bring home the day before leaving to come home. When I got home, I was exhausted, and the fish weren't acclimated until the next morning. So they were in that fish bag for 2 days! I made sure the temp stayed constant by putting the bags in a cooler, and they were fine! With the partial water changes you will be doing, they should be okay. The airstone will help a lot also. The air pumps are around $7.00 or $8.00 and invaluable. They have them at PetSmart. Most fish or pet stores will have them.
