This is for 4 crayfish, 2 males and 2 females.
Dwarf crayfish are also called Mexican Dwarf Crayfish or Mexican Mini-Lobsters because they are mainly found in the lakes, rivers, and streams of - you probably guessed it - Mexico, as well as southern areas of the United States. The small size and fairly peaceful nature of these crayfish make them more suitable for community tanks than their larger relatives. While they get along with a much larger variety of tankmates than large crayfish, they may still pick on snails and very small fish or shrimp. They have been known to live up to 2 to 3 years on average.