Calcium deficiency is a major dietary problem in captive reptiles. Exo Terra Calcium + D3 Powder Supplement contains high levels of phosphorus-free calcium as well as balanced amounts of vitamin D3 for optimal calcium absorption and to help ensure long-term health. Vitamin D3 aids in the proper absorption of calcium and is vital for captive reptiles not exposed to natural sunlight or ultraviolet lights. Exo Terra Calcium + D3 Powder Supplement is a complementary food for reptiles. Vegetables and Fruit: Blend 1/2 tablespoon of Exo Terra Calcium + D3 Powder Supplement with 1/2 tablespoon of Exo Terra Multi Vitamin Powder Supplement per 500g mixed vegetables and fruits. Always provide clean fresh drinking water. Insects: Thoroughly mix a 1:1 ratio of Exo Terra Calcium + D3 Powder Supplement and Exo Terra Multi Vitamin Powder Supplement in a container and add live insects. Cover and shake gently until all insects are “coated”. No other supplementation is required. Always provide clean fresh drinking water.