My tank in my egrip is just about empty and I have a new flavor that I want to use. Is there something I need to do to get the old flavor out so the flavors don't clash together and ruin the new flavor? This will be the first time refilling the tank other than when it was first filled at purchase. If anyone has experience with this mod or if its similar to other devices with a built in tank please help a guy out. Really want to vape some blue voodoo without messing something up. Thanks