top of page

 Freshwater Crabs : 

These crabs spend most, if not all of their time in water. They can and do prey on fish if they can catch them, but the smaller varieties are peaceful in a community tank, provided none of their tank mates rest on the bottom (like neon tetra). They prefer to have brackish water, although they will tolerate freshwater if a little salt is added, and are best suited in a palludarium set-up. In the wild they usually move from brackish to freshwater areas, but they march back to more brackish waters or even the sea in order release their eggs. They need an omnivorous diet of shrimp pellets, fruits, vegetables, shellfish, blood worm and other commercially available frozen foods, and will damage plants if not fed alternative greenery.

Beautify Your Tank With Aquarium Crabs:


There are at least two great reasons for adding aquarium crabs to your tank. Crabs help to maintain water quality and they are fascinating to watch. Crabs are scavengers; they eat dead and decaying organic matter including dyeing plants. When you spill too much fish feed into your aquarium the crabs will help you out by eating the excess. An additional benefit is the incredible color crabs can add like the Red Apple Crab or the Purple Vampire Crab. They are also fascinating creatures to watch as they move about your tank foraging.


Crabs make an interesting addition to freshwater aquariums. They enjoy shrimp pellets but they will eat various fish foods. They will eat almost anything including fish carcasses. You might joke that they are the "goats" of the aquarium. When you decide to supplement your aquarium crab’s diet, try sinking Hikari Crab pellets as well as Hikari Algae Wafers.


As far as habitat is concerned you may want to provide several places for your aquarium crab to hide. They enjoy hiding so make sure to offer plenty of shelters, especially if you have more than one crab. Don't be surprised if your crab tries to move gravel around on the bottom of the tank to form mounds or valleys to simulate a burrow. This makes them a lot of fun to watch and interesting members of your tank. You will want to keep you’re a good lid on the aquarium because crabs may try to climb out and will not survive outside.


Aquarium crabs aren’t as hard to keep as you may initially think. One of the most important things you need to consider is to make sure not to keep more than one or two in a small tank (less than 25 gallons). They can be very aggressive and maim each other, especially when they molt. Many people think they are too aggressive to keep with fish, but many crabs such as the Panther Crab do well with small fast fish like Tetras, Neons or Guppies.










Freshwater aquarium crabs can be kept by themselves or within a community tank with other fish. You have many great choices for a freshwater aquarium, attractive for their interesting looks and behaviors or their scavenging tendencies. Most crabs serve as a cleanup crew for an aquarium, removing the leftover fish food, decaying plant matter and other fishy buildup from the bottom of the aquarium.


Red-Clawed Crabs:


The red-clawed crab is a popular one. It thrives best in brackish water with fish that will not try to eat the crab. Red-clawed crabs grow to up to 2.5 inches and live about four years. They are not picky when it comes to food and make great scavengers, but you may need to offer a dry food or vegetable to supplement their diet. Be careful about keeping the lid on tight, because the red-clawed crab may try to escape.


-Experience level: Beginner

-Tank Setup: 20+ gallons

-Diet: Frozen, Pellets

-Maximum size: 2"

-Water temperature: 72-82°

-Swimming level: Bottom


Note: Pet availability is seasonal. State and local regulations may vary. Pricing may vary by store location. PetSmart stores cannot match the price above for this pet. Ask a store associate for details.


Red clawed crabs are fun, fascinating little creatures that make great pets for your home or classroom. They are easy and economical to care for and their crabby antics like climbing, digging, molting and shell switching are as entertaining as they are educational.


These crabs love to climb, so be sure to have a secure lid on your habitat. They use fine hairs on their legs to scavenge for food in their bedding or substrate. One of the most fascinating features of these critters is molting, or shedding their outside skin in order to grow. Be sure to provide lots of hiding places like rocks or driftwood so they have plenty of places to hide and feel secure.




Bottom swimmers
You will see crabs swimming at the bottom of your aquarium or climbing on the décor.


This is a characteristic of crabs and means they need to shed their outer skin in order to grow.


Hiding places should be offered as crabs prefer a secure area as a retreat.


Juvenile crabs can be kept in a general community aquarium, but as adults they may harass their tank mates and should be kept by themselves or with other large, tough fish.


Staple diet
Crabs must be fed sinking pellet foods that they can find at the bottom of the tank.


Frequent feedings
For optimum health, feed your crab as much food as he will consume in 1-3 minutes, twice a day.


Vet Assured™ Promise
All pets purchased at PetSmart are raised under our exclusive Vet Assured program and come with a 14-day satisfaction guarantee. Vet Assured is a program designed by PetSmart veterinarians to improve the health and well-being of our pets. The program sets standards for the care of our pets by our live animal partners and store associates and establishes strict standards for the monitoring and prevention of common illnesses found in pets. PetSmart makes a significant investment in the care of our pets and it is apparent in the quality and comfort of the pets in our stores. However, if your pet becomes ill during this initial 14-day period, or if you're not satisfied with your pet for any reason, PetSmart will gladly replace the pet or refund the purchase price. Please keep your sales receipt and return the pet to the store where it was purchased if needed.




Red Claw Crab Factoids:



Origin : Thailand, Singapore, Hong Kong

Maximum Size  : 1.5 inches plus claws most likely but up to 2.0 inches

Longevity  : Probably 1.5 to 2 years

Housing  : Prefers about a square foot

Security  : Burrows under anything

Temperature :  Prefers 72 to 82 but flexible both ways

Attitude  : Hider.  Active at night.  Likes to climb out and run like a roach.

Foods  : Beach-combing scavengers.  Not even slightly picky.

Water : Needs clean water .  Add a "pinch" of salt


Red claw crab.  Mean and pinchy.  Likes to hide even more than most crabs.  Pretty.  Male

Origins.  No one really breeds these nippy little critters, so they still come from Thailand, Singapore, and Hong Kong -- major fish exporting areas.  We usually get ours out of Chicago (east of here but not far east).  We used to call them “red Thai crabs” because we were brought up that way.  However, since they’re not really “red,” the red claw appellation seems more apropos. And if you search for “red Thai crabs” on the web, you’ll find 69,000 ways to cook red saltwater crabs from Thailand.


Attitude. :  If you have a rock, piece of wood, or ceramic ornament in your tank, your red claw crab will zero under it pronto.  Males like to argue.  Both sexes like to explore at night.  They work harder to escape than Steve McQueen.  Red claw crabs shinny up your air line tubing and hit the ground running.  Ditto if you net them.  They scurry right out of your net and skitter across your floor and away from you.  If you grab yours by hand, they usually grab you right back.  Then you give them a JATO and they still hit the ground running.

Red claw crabs proving the "Crabs in a bucket can't escape" legend.

We watched this little red claw crab pick off and eat tiny pieces of wood.

Here's a red claw crab running off with a piece of green bean.

And fish belong on every crab's menu.

Doctors recommend seafood at least twice a week.

Here's a romantic seafood dinner for two.

Red Claw Crab Foods.  These little guys and gals eat both flotsam AND jetsam PLUS the salad bar.  Whatever they find, they try to eat.  They may have preferences, but they pretty much eat whatever you give them.  Do not fall asleep on their beach.  You can mix them with most community fish.  Avoid long-finned fish, slow-moving fish, and bottom-dwelling fish.


Compare and Contrast.  Think of these cute little guys as Thailand’s version of our American crayfish.  The contrasts are their shape, price, accessibility at your local bait house, and a dash of salt in your red claw crab water.  If you can keep crawdads, you can keep red claw crabs. 

Careful how you grab red claw crabs.  They'll grab you back (hard) if they can reach you.

Water Conditions.  Any critter with an exoskeleton will prefer harder water -- not a problem in Des Moines.  Red claw crabs will get along without salt but seem to do better with it.  Add a teaspoon of salt per gallon -- approximately -- we’re not talking rocket surgery here.  Artificial sea salt has lots of ingredients and could be better than plain salt.  Avoid table salt.  It clouds the water, and as Mike says, “we don’t sell table salt.” 

Remember, the bigger the pincers, the bigger the pinch.  Can you see the tiny "hairs?"

Males in foreground.  Females in background.

Sexing Red Claw Crabs.  It probably machts nichts, because you’re unlikely to breed your red claw crabs.  However, males have larger and redder claws and slightly larger bodies.  Females have smaller claws (but still pinch).  y.  Male

And if you just have one red claw crab, your chances of breeding decrease considerably.

Best way to pick up a red claw crab.  Don't try this at home.

How to Pick up a Red Claw Crab.  In spite of these pictures of a highly trained specialist grabbing and holding onto these picnchy pests, you’ll be way ahead to use a net.  Red claw crabs don’t latch on like a baseball-size hermit crab ... but they CAN startle you and cause you to fling or drop your crabby little buddy.

You want red claw crabs that scamper away from you, not mopey ones.

Pick a red claw crab that looks perkier than this.

Hiders.  Red claw crabs zip under any objects in their area.  Seems you can always find the most intriguing critters under rocks and fallen logs.  If you want to see these crabs in action, you need to keep several in spite of the “two per ten gallon tank” rule that appears in public parlance.  Fuhgettaboutit.  Live life on the edge.  Put a half dozen in there and enjoy.

Brand new white sand floats for days.  Plan ahead.

Substrate.  Immaterial to your red claw crab, however you want to put them over something they do not blend into.  White sand has some disadvantages, but it really shows off your crabs.

Red claw crab biotope with no hiding places.  Those strands of Java moss won't last long.

Two days after introduction, 11 red claw crabs generated this much crab crap on the white sand.

Close up of the bogwood in their tank.  It does not float and offers access to the surface.

He's red claw crab "king of the hill" -- at least for an hour.


Container.  You will need a working lid.  Red claw crabs want to climb out.  They also like access to air every so often.  However, with a little homemade ingenuity, you can come up with housing that keeps the little rascals visible -- at least most of the time.  

Pugnacious little rascals.


Last Words.  Try red claw crabs.  They’re fun..


Courtesy to : 

Fiddler Crabs : 


The fiddler crab is also referred to as a mini crab. The species thrives best in water that is slightly brackish and in an aquarium with an internal filter. Mini crabs will grow to up to 2 inches. They are usually peaceful crabs that are fairly easy to care for; they can be quite interesting to watch while they are scavenging for food. Fiddler crabs spend most of their time climbing and hiding in driftwood, rocks and other decorations on the aquarium floor.


Origin  :  Florida marsh lands mostly

Maximum Size  : 1.5 inches plus claws

Longevity : 1.5 years

Housing : Prefers about a square foot

Security : Digs tunnels or burrows under anything

Temperature : Prefers 75 to 82o

Attitude : Likes to climb

Foods : Beach combing scavengers

Water : Needs clean water


Three female fiddler crabs above.  Male below.  Shells an inch across.

Origins:  These crabby little guys inhabit the shores of Florida. Their scavenging helps keep Florida’s coasts clean.  Fiddler crabs eat algae in the wild.  Anything you give them will be more nutritious.

Male fiddler crabs can be left-handed or right-handed.

Name:  “Uca” comes from the name the local Seminoles called the little scudders.  We call them “fiddlers” because that big claw the males wave around looks exactly like the 1684 Stradivarius mini-violin that Antonio Stradivari made for his second son – the one who played second fiddle.

Two eyeballs.  Big claw for the ladies.  Little claw for food.  He has his priorities straight.

Male fiddler crab in back checking out the comely lass in the foreground.

Males in the Wild:  Male fiddler crabs dig deep burrows in the mud.  When the tide approaches (twice a day), they pull a lid over their burrow and retreat into the safety of their little hidey-holes. As the water withdraws, they flip their lids and start looking for algae and fiddler babes.  When they see a female, they start waving that big claw around and making kissy-kissy noises (actually, rattling their big claw against their burrow walls) in hopes of coaxing one of the nubile female crabs into their boudoir to look at their etchings.

In sand, fiddler crabs have no problem digging burrows.

Females in the Wild:  Female fiddler crabs also dig burrows and come out when the tide recedes to look for algae and guys with big claws.


Threats in the Wild:  Big wading birds love tasty little fiddler crabs.  Turtles ditto.  Also raccoons and big frogs and toads.  Not too many restaurants tho serve fiddler crabs on their menu.  Indoors, their main threat is climbing out and drying out.



Fiddler crabs often get shipped with these Styrofoam "peanuts."

Water Conditions:  Add a teaspoon of salt per gallon of water. Change your fiddler crab water often.

She's playing "Queen of the Mountain."  The male fiddler crabs are arguing.

Female fiddler crabs are usually smaller than the males.

Like to Climb:  Male fiddler crabs seek out high points in their cage so they can wave at more females.  They can also climb out of their cage unless you cover it securely.

Big claw.  Eyes on stalks.  Mouth in the middle of his chest.  Hairy legs.  Very sexy.

Size:   We call them mini-crabs because they top out at about 1.5 inches – plus that great big claw on the male fiddler crabs.

Change that food daily before it spoils.

Foods:  Most important, provide their food in a shallow dish – one they can get in and out of easily.  Hermit crab food works great. Probably anything you give them will work.  Change their food daily.  Once most foods get wet, they start growing moldy and … oh, wait, they eat that too.  But you want a cage that smells clean, so change their food daily.  You for sure want to avoid providing a home for those pesky gnat-like flitterbys that always find smelly food.  Fiddler crabs eat surprisingly daintily.  They pick up each tiny speck of food and carefully place it into their mouths -- unlike the larger crabs that greedily grab the biggest chunks they can find and run off with them.

Fiddler crabs actually blend into multi-colored gravels.  Choose a contrasting color.

Is this a May Day dance?

Space Requirements:  In small groups your fiddler crabs will want a square foot of space each.  When you crowd them like we do, they seem to lose interest in arguing.  They’ll act more naturally (argue more) in smaller herds.


Breeding:  If the male fiddler crab coaxed a female into his burrow for a two-week honeymoon, she will produce numerous eggs (in the thousands) that drift off into the ocean.  Hard to duplicate in the average backyard.

White sand makes an excellent fiddler crab substrate.  They show well.

Substrate Choice:  Dirt, coconut fiber, potting soil, or vermiculite would make a good substrate to burrow into.  Most people use gravel or sand.  Fiddler crabs blend into natural gravels.


Mini-Caves.  Since few cages are tall enough to provide two feet of substrate to burrow into, you may want to give your fiddler crab a mini-cave or at least an object to dig under.

Harmless little mini-critters that clean the beaches.

Tank Mates:  You can mix them with equal-sized non-violent terrarium residents.  Anoles, fire-belly toads, newts, dwarf African frogs come to mind.  Even tho those big claws look formidable, these guys are not crayfish.  You can pick them up with impunity (or with a net if you are fresh out of impunity).  Cover your net.  Fiddler crabs skitter out of a net in an instamante.

Bits of decor also give your fiddler crabs more room to roam.

Plants:  Immaterial to the crabs, but planted tanks (even plastic plants) make their biotope look better to us.  Feng shui does not seem to apply to fiddler crabs.

You won't want to run this many head of fiddler crabs on your own crab ranch.

♫ "Mr. Sandman, bring me a dream..." ♫

We're teaching Buster (Buster Crabbe, get it?) to wave goodbye.

Last Word:  If you hear strange sounds coming from your fiddler crab corral at night, relax.  Your fiddler crabs are just fiddling around. 


Courtesy to : 

Gold Claw Crabs : 


Gold claw crabs have one claw larger than the other and will wave it at other crabs to communicate and as part of its mating ritual. These crabs live up to 2 years, as long as the water is kept clean and plenty of decaying material is available for them to scavenge. This is a small crab species, topping out at 1.5 inches, but it can be somewhat aggressive with tank mates. Gold claw crabs need some land in their environment, but be careful of the aquarium lid, because they will escape.

Soap Dish Crabs : 


The soap dish crab gets its name because it is often shipped in a soap dish, each crab by itself to prevent one from killing another. It has many aliases, being called rainbow crab, moon crab, patriot crab and other names. These crabs can be quite aggressive, and will eat other crabs and fish. Many fish keepers still enjoy them because of their brightly colored bodies, feeding them live fish, black worms, shrimp and other creatures. These crabs thrive best in brackish water.


Soap Dish Crabs:  Importers ship soap dish crabs individually in (oddly enough) soap dishes.  This keeps them from killing each other.  They are not good mixers.



Watermelon Crabs : 


Habitat: Western Pacific – China, Japan, Philippines, Thailand, Indonesia, Papa New Guinea, Melanesia, Micronesia
Status: Not Evaluated


This gorgeous crustacean is called a Watermelon Fiddler Crab (Uca crassipes) due to its unique coloration which resembles, you guessed it, that of a watermelon!


Fiddler crabs make up approximately 100 species of semi-terrestrial marine crabs that are distinguished by their own over-sized claw positioned opposite to a tinier, meeker-looking claw. Fiddler crabs get their names from the movement of the smaller claw to the animal’s mouth when eating – it looks like the smaller claw is playing the larger one, just like a fiddle!

Watermelon Fiddler Crabs , like other fiddler crabs, use their big claw in ritualized combat during courtship of a female by signaling their intentions to other crabs. A large claw may be lost in battle, but no matter because these guys are able to regrow a new claw after their next molt. The process is a little odd however, because the new, larger claw will actually form from the original small claw (it will just increase in size) and the lost claw will become the small claw. The big claw basically switches sides if lost. Either way, a big claw is a big claw!

Less colorful brownish version of the "soap dish crab.".

This guy's better looking.  Still a great pincher.

Soap dish crabs put the "crab" into crabby disposition.

Don't try this with a live soap dish crab.

Soap Dish Crabs eat fish and anything else that gets close – including each other.  You cannot mix them with anything.  They’re beautiful and come in four colors:  red, yellow, orange, and purple.  Just remember that these colorful crabs are efficient killers.  Keep them by themselves. They get their names from the way they’re shipped into our country. Each one gets packed into its own, individual soap dish.  That’s the way their captors keep them from killing each other.

Yes, they eat mollies and other fishes.

Rusty Crabs: 

      Also great at pinching, these little guys will survive in deep water.  Do not trust them around fish.  Kinda drab little critters.

Mosaic Crab:

    We know little about these guys.  They just showed up recently.  We can’t see the “mosaic pattern.”  Maybe it’s like the Mosaic code.  We treat them like red Thai crabs.

King Crabs :


Are a new crab to us (2005).  They pinch.  They stay small.  They argue/fight with each other.  They eat whatever you give them -- just like nearly every other crab.  They are drabber than most crabs and not as economical as most crabs..

Red Thai Crab  :


   You probably suspect where these little inch and a halfers come from.  They can easily snag your fishes.  They will snag you also.  Handle them carefully.  Pretty pincers.

bottom of page