I know this has probably been covered. But just wanted those who desire a tangier flavor for thier eliquids to know that I love this stuff. It's from LoRann's and it really does do wonders for fruit flavors.
https://www.lorannoils.com/p-9000-tart-sour-flavor-boost.aspx
https://www.lorannoils.com/p-9000-tart-sour-flavor-boost.aspx