Caribsea Caribsea Ohko Dragon Stone Freshwater Rock (25 lb) Box - Caribsea $69.95 The Ohko stone, Aquarium Rocks (Dragon Stone) is a rock that resembles dragon scales. It typically has a greenish brown coloring and is very light weight compared to other hardscape stones. Aquascapers say the Ohko stone is basically composed of hardened... Add to Cart