Shrimp Accessories - Stacks The aquavitro Shrimp Accessories - Stacks are the perfect addition to any aquarium housing various shrimp species. As with many smaller fish species, shrimp require secluded and protected spots in the aquarium as a way to avoid predation from other animals, protect their sensitive exoskeletons after molting and to aid in the breeding cycle. Often, when female shrimp are berried (have eggs) and do not have adequate refuge, the stress will cause them to drop and abandon their eggs. Coming in a pack of 3, the small stacks are similar to the shrimp pipes, but sport a unique belled end like a chimney and can be stacked for larger installations and more diverse placement. Easily blending in to your established aquarium decor, the durable shrimp stacks offer a quiet, shaded area for your shrimp to rest and relax. Additionally, these structures provide additional surface area that is ideal for the growth of development of fine algae or biofilm, which is a critically important food source for many species of small shrimp.