tiny shrimp occupy anchialine pools. These are puddles or ponds located near shores and surrounded with lava rock. The pores and chambers of the lava allow seawater to seep into the pools, where it mixes with freshwater from springs or rain. Anchialine shrimp are noted for their great adaptability: they survive in pools of undiluted seawater and in brackish ponds; they tolerate water temperatures over 85 degrees Fahrenheit (near 30 degrees C) when the tropical sun heats up the shallowest anchialine pools, and they also thrive in cool water. Prior to 2003, the EcoSpheres contained at least one snail at the time of purchase. However, the system is self-sustaining without the snails. (The main function of the snails was aesthetic, as they cleaned scum from the glass.) The Gorgonia coral in EcoSpheres is dead and plays no active biological role in the system, however it does increase the surface area for beneficial bacteria and algae, and the calcium carbonate in the coral acts as a pH buffering agent. Concerns A major concern is that the shrimp’s sole habitat is shrinking, with over 90% of Hawaii’s anchialine pools having disappeared due to development, and this species of shrimp is disappearing along with them. Comparable objects and systems Commercially packaged aquarium kits, including algae, anchialine be left open or closed, are available in Hawaii. The customer can combine these to create an aquarium comparable to the EcoSphere. It is possible to purchase Halocaridina shrimp from Hawaiian aquarium dealers and create home-made sealed aquaria with no other special supplies. Sand, gravel, crushed shell, and very well cycled filtered water from a successful saltwater aquarium, with the lowest attainable ammonia content, should be used. A small inoculation of live Spirulina algae may be introduced. Certain ubiquitous algae and bacteria are likely to be carried by the shrimp themselves and will soon colonize the walls of the container. There is a risk that pathogens also may be introduced. The Ecosphere can degrade with time. It is "self-sustaining" in comparison to systems which degrade much more quickly. The advantage of an aquarium closed with a lid (rather than a permanently sealed plug, which is found in the base of an EcoSphere) is that if the system goes out of equilibrium, the owner can remedy conditions and prevent a complete die-off. Intervention to maintain good water quality allows a larger number of shrimp to live in the