Rim a glass with salt: Rub a lime wedge along the rim of the glass and dip it into a plate of salt, coating the rim evenly (optional).
Fill the glass with ice cubes.
In a shaker or mixing glass, combine the non-alcoholic tequila substitute, grapefruit juice, lime juice, and simple syrup (if using). Add ice to the shaker and shake well to combine the ingredients.
Strain the mixture into the prepared glass filled with ice.
Top off the glass with soda water.
Give it a gentle stir to incorporate the soda water.
Garnish the drink with a grapefruit slice or a lime wedge.
Serve and enjoy your Virgin Paloma Mocktail with flavors reminiscent of the traditional cocktail!