Advantages and Disadvantages of HYDRUS Watercolor Concentrates February 1, 2017 Welcher https://www.youtube.com/watch?v=dL-xi1GhGY4This video, https://www.youtube.com/watch?v=dL-xi1GhGY4, can also be seen at https://www.youtube.com/channel/UCO1i2JmrYr2rgLa8vYRrnFg.