Nah but definitely buy live rock, and the higher quality the better, and the more surprises, or hitch hikers. Ive got tons of stuff growing on mine, seaweed, TONS of coralline algae [purple, orange] little bright green plants, and even these little shiny greenish balls that feel like glass and they grow, its cool, plus a crab. Also, make sure to do the mushroom thing. One time I got a rock with 3 clams, tons of mushrooms, the biggest 1 of which grew inside of an old clam shell, 5 feather dusters, and another 1 of those little green balls, all for $25! Theyre definitely a bargain in my opinion.