Products that contain Calcium (e.g. Vitamin B+ Performance) or Magnesium in the VÖOST Effervescent range tend to leave a bit of sediment in the glass.This is not a product fault but more the nature of any of our products that contain Magnesium Carbonate or Calcium Carbonate as active ingredients.These ingredients are known for water insoluble properties, which can in some cases result in residue. Don't worry though - you're still getting your full dose of vitamins and minerals!