Should I change the gauge of my guitar strings?

Basically, if you are tuning a string sharp, it is best to use a lighter gauge to prevent too much tension making the string snap, and if you are tuning flat, you need a heavier string to stop it from going too floppy. I would use maybe a 20 for the G, and a 53/54 for the low E. You may have problems with the G going floppy and the E being really tight when you tune to standard tuning again.