How to Breed Emerald Crabs

Emerald crabs are attractive additions to your saltwater aquarium, but may present some problems when it comes to propagating them. Part of the problem lies with their tendency toward aggression and territoriality to one another in a small tank. For this reason, if you want to have a potentially breeding population, it's a good idea to have an aquarium larger than 55 gallons with plenty of rock hiding places. Even then, you can only present the ideal conditions in which the emerald crabs can mate, but you should not expect great amounts of success. In short, it is as much a matter of luck in producing breeding emerald crabs as it is preparation.

Things You'll Need

  • Specimen saltwater aquarium minimum 55 gallons
  • Ocean salt
  • Aquarium water test kit
  • Selection of live rock and inert rock
  • Bubble algae
  • Freeze dried shrimp pellets
Show More

Instructions

    • 1

      Set up the aquarium in an unobtrusive place where you can culture the bubble algae that comprise the emerald crab;s food. Use caution, however, as this form of algae is detrimental to reef tanks and highly invasive. Always wash your hands thoroughly if you have been handling water with bubble algae before you handle the water in your regular tank.

    • 2

      Set up the salinity of the tank by mixing enough synthetic ocean salt to read 1.021 on a refractometer. This will ideally replicate the mineral content of the water in the ocean. Install an adjustable water heater into the tank and set its temperature for precisely 75 degrees. Allow the tank to mature for three to five days.

    • 3

      Test the water with an aquarium test kit to ensure that its pH level is between 8.1 and 8.4. The optimal pH level is 8.2 for these crabs.

    • 4

      Add a selection of both live and inert rock to the aquarium, but don't worry about adding gravel or other substrate. As long as there is enough hiding places for the individual crabs, they won't venture out much from their hiding spots, anyway.

    • 5

      Culture the bubble algae in a low-light condition, avoiding lighting that fully replicates sunlight. This would cause the algae to quickly overrun the tank even with natural herbivores such as emerald crabs in abundance. To culture the algae, you need do little more than introduce a few spores to the tank. They will grow quickly by themselves in the right lighting conditions.

    • 6

      Add four to five mature emerald crabs to the tank for every 20 gallons of water capacity. It is helpful if you can purchase all of these crabs from the same retailer or distributor. This concentration, while edging on overcrowding the territorial crabs, gives you the greatest chance of obtaining a mix of both males and females, which are difficult to sex.

    • 7

      Watch carefully to make certain that the crabs are focused on eating the bubble algae and are not paying much attention to one another. If the bubble algae food source begins to run out, add freeze-dried shrimp to the tank to provide additional protein. With time, and if you maintain the correct pH balance in the tank, the emerald crabs will release their . When this happens, the young will feed on the bubble algae, but add plankton to the tank as well as soon as you notice that the emerald crabs are releasing their young.