Looking to add some diversity to your fish tank? Turn your attention to freshwater crustaceans. Not only are these hard-shelled critters interesting to observe, but they can also play a critical role in keeping your tank’s ecosystem stable. For instance, ghost shrimp will eat food that’s fallen to the bottom of the tank, limiting how much ammonia is produced through decomposition. Crayfish won’t hesitate to eat sick fish near the tank’s bottom, which can mitigate the spread of disease.
Here are some freshwater crustaceans that can make great pets.
1. Crayfish Have Lively Personalities
Crayfish (also called “crawdads” or “crawfish”) make fascinating additions to aquariums with plenty of floor space. They spend their days burrowing, creating small mountains out of gravel, and chasing away fish that get too close. Believe it or not, crayfish also have lively personalities that help them stand out as individuals. Note: while crayfish can inhabit the same aquarium, they need hiding places to avoid too much contact with one another. Crayfish are very territorial and will fight to the death if threatened.
You have some flexibility when creating the ideal conditions for a pet crawfish. Crayfish need a minimum of 20 gallons each, with enough water to submerge the animal (so about six inches deep). Because crayfish can’t swim around like fish, they’ll need sufficient aeration to circulate oxygen throughout the tank, including where they generally rest at the bottom. They prefer water with a neutral pH (7.0), although you should treat the water with conditioner to remove any chemicals, such as chlorine.
Feeding a crayfish is one of the most delightful parts of owning them. While they get adequate nutrition from shrimp pellets, they also enjoy frozen peas.
2. Ghost Shrimp Handle Leftover Tank Waste
Move over plecos—there are some new aquarium cleaners in town! Ghost shrimp are semi-translucent shrimp that mostly feed on leftover food that fish don’t eat. In the long run, this can help to stabilize your aquarium’s water parameters and reduce how often you must clean it. While ghost shrimp aren’t as vibrant as crayfish, they add to the aquarium’s diversity. They spend most of their time avoiding fish or digging in substrate.
These unique aquatic creatures do well in tanks with small, non-aggressive fish. Larger fish, like goldfish, will likely eat these little guys without hesitation. Many people enjoy keeping ghost shrimp in their own separate tank because they breed quickly, and it’s fun to watch the miracle of life. Keep in mind that while ghost shrimp are fairly hardy, they’re not immune to severe temperature fluctuations or changes in water quality. Be careful administering any medication to your fish containing copper, as this could prove fatal.
3. Freshwater Crabs Thrive on Land and Water
There are many varieties of freshwater crabs that do well in aquariums. Keep in mind, however, that many species need a means of reaching the surface so they can breathe. You can do this by creating a small mound with gravel or using a tank decoration that your crab can climb on. You may also consider purchasing a paludarium, which is an aquarium that allows for both land and water-dwelling critters.
Note that while some crabs can live in freshwater, others need some level of salinity to survive. Take the red claw crab, for example. These crustaceans need brackish water, meaning water that has some salt in it. Various care guides online recommend pouring a spoonful of salt into the crabs’ water supply, then testing it soon after to ensure it mimics the crab’s natural environment.
4. Vampire Shrimp Are a Non-Aggressive Species
Crayfish fight to the death. Some crabs will gorge themselves on an aquarium’s small fish. Is there any small freshwater crustacean that doesn’t attack its tankmates? There is: meet the vampire shrimp. Despite the name, the vampire shrimp isn’t a bloodsucking creature; rather, it gets its name from its nocturnal feeding habits, along with its fang-like appendages. It does not pursue other fish for food and usually remains hidden under rocks or foliage. A hardy species, the vampire shrimp can live more than five years with proper care, thriving in aquariums that are no more than 84 degrees Fahrenheit.
While many aquarists consider vampire shrimp great additions, they can be hard to source. While you can shop online or visit specialized pet stores, you may still come up empty-handed. In that case, you may want to set your sights instead on ghost shrimp, which sometimes sell for literally a dime a dozen.
Honorable Mention: Hermit Crabs Make Great Starter Pets
If you tossed a hermit crab into your freshwater aquarium, chances are, it would drown. That’s because, like many crustaceans, hermit crabs need air to breathe. Yet, if you purchase an appropriately designed paludarium, you could keep both fish and hermit crabs in the same enclosure. Your hermit crab would mostly occupy the land area, then go for an occasional dip in the submerged area.
Hermit crabs need both freshwater and saltwater to survive. Many aquarists love these little guys because they’re one of many animals that live in shells. Some even design shells with smiley faces, sports team logos, and other images to give their hermit crab extra flair. With the right conditions, a hermit crab can live for 20 years! Unfortunately, many never live beyond a few months because of improper care.
Always do your research when bringing home a new animal, whether it’s a fish or crustacean. Even something seemingly small, like tank size, could make a huge difference in your pets’ longevity.
