I know nothing about nic...I'm a noob about that. Can you elaborate on that?
Nic concentration is generally measured in mg/ml. Occasionally by percentages.
There is unprotonated nic and “salt” or protonated nic. There are many different chemicals that are collectively called “salt nic” but they are generally unprotonated nic reacted with some mild acid or another.
I don’t deal with “salt” nic at all myself. Afaik there is functionally zero research on its safety. Everything below is about traditional unprotonated nic.
truely pure nic is somewhere near ~1000mg/ml and is very very dangerous. The lower the molarity the easier it is to work with though.
The highest concentration I generally work with is 100mg/ml. 1/10th pure. The highest I’ve seen generally recommended to actually vape is 24mg/ml. This is quite strong, but not as strong as some protonated mixtures which can be double that.
Myself I vape 18-20mg/ml Mtl or 5-10mg/ml DL. These numbers are quite unusually high for a long term ecig smoker. Desire for nicotine generally reduces over time.
The mg/ml number is useful because if you know how many mls of juice you have you also know how many mgs of nicotine you have. To raise a 6mg/ml bottle of juice to 18mg/ml you have to more or less triple the nic content. A 30mlbottle of juice (which is full) at 6mg/ml will have about 180mg of nic in the bottle. That would need to increase to 540mg. What makes things complicated is while that is less than half a ml of pure nic, pure nic is wildly unsafe. Using 100mg/ml liquid it would take the addition of 5.4ml, which is easily enough to overflow the bottle and change the numbers since you don’t have 30ml anymore you have 35.4ml