And toast, about the carts. I have a baggie that holds my used carts that are now frayed or just used a lot for days. Periodically I take those used carts, pull the wet fillers out and put them into a 10 mL syringe barrel. There may be 20 of them. Then I put in the plunger, and press the liquid into an empty dropper bottle. This juice can, depending on what you have been vaping recently, be excellent or not. Sometimes it becomes my current favorite, and its like getting a free day or so of vaping (not the DIY vaping is expensive). The filler material compressed in the syringe can be removed with long tweezers or a thin chopstick works too, and the filler material can be soaked along with the empty carts in 100 proof vodka, removed and dried, and often can be reused. The vodka will sterilize everything pretty well.
Vape proud!