This package is ideal for reef aquariums up to 50 gallons. It contains a carefully selected mix of herbivores, detritivores, and omnivores. By utilizing these cleaning organisms, and good overall husbandry practices, aquariusts will minimize their algae and detritus cleaning responsibilities. This Cleaner Package has 15 Scarlet Hermit Crabs, 30 Astraea Snails, 20 Cerith Snails, 10 Super Tonga Nassarius Snails, and 2 Mexican Turbo Snails. For larger aquariums just order multiple quantities of this package accordingly.