Yeh its not really an issue. It will mean you're nic level will be a slightly lower than 18mg/ml but probably not even noticeable.
One that might satisfy both chocolate and vanilla - Cookies & Cream 12% FW Cookies & Cream 2% Vanilla 2% EM EM is Ethyl Maltol aka Cotton...
New tanks I give them a hot bath in my ultrasonic cleaner (from Aldi for 20-25 bucks) for 5 mins. Changing flavours I give top part (not coil...
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