I did one with aquarium silicone as a sealant, figured safe for fish, safe for me. Still
vaping it 2 months later. Just use either your finger or a flat wooden stick to spread a very thin layer of the sealant - works best if you wet your finger or the stick in water first but, you can always peel the silicone off your finger later too.
Not sure if the juice will eventually degrade the sealant, but it doesn't appear to be doing that so far.