The Red Graciliaria Macroalgae is a reddish transparent alga that is a natural food source for herbivorous fish. The Red Graciliaria Macroalgae is the favorite food for tangs, angelfishes, and makes a valuable addition to any reef tank. They require nutrition and lighting, and therefore additional supplements help in their continued growth. They are widely distributed, aquacultured and harvested in the United States. The Red Graciliaria Macroalgae is a hardy, sub-tidal red algae that attaches to limestone or occasionally to basalt substrates. If it is to be added in the tank for feeding purposes and requires in large quantities, it is best to grow this Red Graciliaria Macroalgae in a refugium or in a separate tank. For its growth it requires a 12 hour lighting schedule with a 23 watt 6.5K bulb in a 5 gallon bucket. Also, Nitrates of 20ppm and phosphates of 1 ppm are required. Not only this, it is very important to change the water on every harvest to replenish any elements that may have been taken up by the macroalgae. It is a very healthy as well as effective food for tangs and other fishes. You will receive a portion size of a filled 16 oz cup / a handful of macroalage with this product as viewed in the picture above.