I have hand collected some live seaweed and had it for two months now, it is doing fine in my sea monkey tank, I reccomend it in saltwater carnivore tanks (lionfish, morays, cleanerfish, etc) not in saltwater herbivore tanks (angelfish, tangs, parrotfish, sea limpets, periwinkles, etc) because my tangs, snails, parrots and angels love it (for food).