Description
Absorbent felt squares that have been saturated with copper sulfate and dried. Adding one square to the water in the Classroom Plant Watering System (item #158974) will prevent algal growth. Pack of 2.
Absorbent felt squares that have been saturated with copper sulfate and dried. Adding one square to the water in the Classroom Plant Watering System (item #158974) will prevent algal growth. Pack of 2.