Thank you for your interest! Unlike watercolor, liquid acrylic is waterproof and lightfast when dry. It is similar to watercolor in that it mixes well with water. I believe the main difference between liquid acrylic and traditional acrylic is the pigment size and/or quality. The liquid acrylic can be used with tools like airbrush and certain pens because the pigments are ground finer, whereas traditional acrylic watered down is likely not recommended for the previous applications mentioned. ☺