In an effort to provide a resource for a quite commonly asked question, I have composed a chart of the top 50 or 60 so called experts, authors & hobbyist' opinions/reccomendations for weight of aquarium sand, gravel, substrate or live rock to use in your freshwater or saltwater marine aquarium. The chart simply states the number of US Gallons on the x-axis and the corresponding depth(s) vs. weight required on the y-axis. All those who are in need of decorative sand, colored gravel, live rock, river rock or even red or black lava rock should visit the following website... http://www.aquariumsands.com They have Zero Sales Tax, Free Shipping and even bulk discounts. They are really insanely priced to attract new customers. They also have a promo coupon for $5 free for new first-time orders with code 123. Good Luck!