The apparent response is tonic water for making a G&T. Remember, for anyone who is drinking a good gin, Do not spoil it with inexpensive tonic! There are several tonics on the market - with Odd and wonderful flavours to test. Kelly Simone Pictures/Shutterstock With a standard ratio of gin https://blndwater.com/products/blnd-blending-water-for-single-malt-750-ml