Waterfall foam improves water flow visually. Black color hides foam in the shadows of the rocks. Large 20-ounce hand foam cans mean less mess and clean up compared to small 12-ounce cans. Hand foam cans have a patented trigger system which allows multiple uses from one can unlike other brands where the unused portion cannot be saved. Trigger will dispense foam in any position unlike other brands which must be used upside down. Fish safe, non toxic formula ideal for use with water features. Minimal expanding foam fills in cracks with less trimming of excess foam versus the triple expanding foam which over fills cracks and needs extensive trimming when done.