Dennerle Shrimp King Active Soil - 4L bag The irregular shaped grains, with a diameter of 1-4 mm also give a natural appearance The dark black colouring provides excellent contrast with the vibrant colours of the shrimps Promotes growth  bacteria, single-cell organisms, single-cell algae and other microorganisms - as valuable, natural nutrition, especially for young shrimps Binds harmful substances for healthy living conditions 4 Liter Bag