Hey Logan!
I generally NEVER pour juice from a tank back into a "fresh" bottle. I'll typically vape it down to almost nothing, and then disassemble, rinse, reassemble and refill. If it's a serious flavor change (menthol to bakery) or something obscure like that, I'll probably pop a new coil (in my PT2s) or if it's rebuildable, I'll pull the wick, dryburn and rewick (making sure to drop some juice on the wick before reassembling. Dry hits = shag-nasty)
If there's less than 1/2 mL, I may just rinse it all out. Pretty much all my tanks are glass now, so at a minimum, I'll soak in cheap vodka (good stuff is fer drinkin'!!!!!)
I remember as a kid, going to the little league fields with my brother, making a beverage called a "suicide" from all the flavors of soda at the concession stand. I've never had the "intestinal fortitude" to do anything like that with my juices

Since I DIY, my "waste cost" is pretty minimal, and I don't mind dumping $0.05-0.10 worth of juice to clean a tank
