Red Food Coloring Test Berkey - Add up to 1/8 teaspoon (10 drops) of artificial red food coloring (must be red) for every 4 liters that your berkey. Web the red food colouring test is only designed for the black berkey™ purification elements and not for the ceramic or other filter. Add 1/8 teaspoon (10 drops) of artificial red food coloring (we recommend. Web how do i perform a red food coloring test?
Web how do i perform a red food coloring test? Add up to 1/8 teaspoon (10 drops) of artificial red food coloring (must be red) for every 4 liters that your berkey. Web the red food colouring test is only designed for the black berkey™ purification elements and not for the ceramic or other filter. Add 1/8 teaspoon (10 drops) of artificial red food coloring (we recommend.