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Common Name: Blue Crayfish, Electric Blue Crayfish, Freshwater Lobster
Latin Name: Procambarus alleni
Origin: United States, Florida, St. John’s River Basin
Temperature: 72-76°F
Ease Of Keeping: Easy, but….
Aggressiveness: Aggressive
Adult Size: 6 to 7 inches (19cm)
Minimum Tank Size: 20gal
Feeding: Omnivore, just about anything they can get their claws on
Breeding: Egglayer, female carries eggs under her carapace
Anecdotes:
The Blue Crayfish is a wonderful addition to any tank, so long as one keeps an eye on it. The only requirements for them in a tank is a cave to hide in during the day, and plenty of plants to climb and hide in. Proper aeration is necessary, as is filtration. They have a reputation for being vicious killers, but as far as I’ve found, the trick is to just watch what you put in there with them. They are very hardy creatures, and they can survive in almost any element. I will lay out some specifics here, to help you keep your crayfish happy and healthy.
Feeding
When it comes to feeding, I’d say your best bet when your crayfish is young would be to start off with some shrimp pellets, but be sure to compliment them with some algae pellets or a slice of zucchini to get some roughage for them, and because it will distract them from devouring any live plants you have in your tank (I learned THAT the hard way). All crustaceans are essentially bottom feeders, so they will really eat just about anything. Crayfish do have a fairly voracious appetite, but make sure you don’t overfeed (see MOLTING, below).
Territory
Territory is VERY important to Crayfish. You really only want to put one in your tank. If your tank is over 50 Gal, you can probably get away with two, so long as they had very definite territories, each with their own cave to hide in, as spaced out as possible. But keep an eye on them, and don’t be surprised if one is clawless after a while; when they fight, they don’t always kill, they usually fight for dominance by ripping their opponent’s claws off. On the upside, single crayfish really don’t need much in the way of space, so long as they’re fed. Just enough so they can roam around a big, and a plant to climb on. I’d recommend putting like two or three feeder fish in with it, such as rosie reds, just in case the Crayfish needs some fresh meat.
Community
Which brings me to my other topic. As far as getting along with other fish, well….I’ve been told Crayfish will eat everything in your tank that they can get their hands on. This isn’t exactly true, but it’s close. I keep mine fairly well fed (I stash a pellet in his cave every other day, and he’s happy), and he only kills other fish if they try to eat his food. As mentioned above, crayfish are bottom feeders, so make sure anything you put in is a middle- or top-feeder. But crayfish also love to climb plants, so middle feeders aren’t completely immune. Plecos are safe around crays because they have armored plating along their back, so tough-scaled fish work well. The other thing to look out for is speed. I have a baby bala shark in my tank (inch and a half…he’s so cute), and he darts around the cray WAY faster than he can catch him. Same with my black skirt tetras.
