Shall I Freeze Nicotine Salt as well, just like free base?
Is it recommended/Ok to use the same Chubby Glass Bottle for different flavors? e.g. if I made grape juice in a bottle, can I wash it later and make another flavor in it?
Also, I have some bottles already of e-juices that I was buying before trying DIY, can I wash them and use to mix my own?
The answer to both your questions is yes.
Salts and freebase are the pretty much the same product. The difference with salts it’s freebase with an acid added to change the PH (different acid depending on what you bought). It should be treated the same as freebase.
I use my bottles over and over till they break and won’t hold liquid anymore. I have bottle’s that are seven years old and still going strong. I run them in hot water clean the liquid out of them then wash them with a mild dish soap and rinse. I turn them upside down to dry the fill them with another mix.
@Chips if you are new to breaking down and/or freezing NIC, make sure to NOT fill the bottles all the way to the top, and leave at least a 1/2" gap. Even though PG and VG will NOT freeze at residential freezer temps, it WILL indeed expand, and contract. MANY years ago I was filling 120ml glass bottles to the top, and capping, and before I got to the last bottle (as the NIC was warming up) I had a cap or two pop. Easy fix, leave at least a 1/2" air gap, and you’ll be fine.