The Environmental Gradient

Cryptic Zones

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A cryptic zone describes habitats or physical areas that recieve almost no light, and very little water current. In nature they occur underneath or within the base areas of coral thickets, within the numerous cracks and crevices, in the caves and tunnels throughout the reef structure and they occur throughout the twilight zone. The twilight zone is the deep bottom area of a tropical reef platform. Establishing a weak light and weak current zone within a captive container is relatively easy, but to establish a cryptic zone that functions properly the aquarists needs to prevent large particulate matter from entering the zone. Barriers are typically used. Large particulate matter can clog cryptic sponges and cryptic squirts. The cryptic zone does not support photosynthesic animals. Animals that have grown within cryptic environments cannot be placed backed into the exposed zone. Cryptic animals lack an ability to shield themselves from UV light. They can also develop very delicate growth forms that are easily damaged in current. Cryptic zones typically shield or shelter these animals from larger predators. Natural and artificial cryptic zones receive inputs of dissolved organics, very fine particulate matter, bacteria and micro-plankton.

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