The first thing you need to know about freshwater aquarium crayfish is that they are a type of invertebrate. These creatures do not have an internal skeletal system – instead, they have an exoskeleton (almost like a shell) that is shed as the crayfish grows. Crayfish can be found in a wide variety of different habitats around the world including freshwater and brackish water. Some species can survive in saltwater for a few days, but there are no marine species of crayfish. Crayfish are also solitary animals that tend to hide in cracks, crevices, and caves – they will also fight off fish and other crayfish that attempt to invade their territory.
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