Tropic Marin USA Bio-Calcium Supplement 18 oz

The ideal source of both calcium carbonate for the corals and carbon dioxide for the zooxanthellae. When Bio-Calcium is dissolved in the aquarium, all 70 trace elements are added and no unnatural by-products are formed. Bio-Calcium powder gets added directly to the flow of water in the sump, refugium or aquarium and cannot be premixed into a concentrated liquid.