To build a visually intriguing and balanced community in your freshwater aquarium, select fish that hangout out at various water depths. Bottom feeder fish not only scurry along the tank's substrate and occasionally pop to the top of the tank for air, but they also tend to be docile. Let's learn more about these desirable tankmates.
How Many Types of Bottom Feeder Fish Are There?
There are many species of fish that spend the majority of their time on the bottom of the fish tank. Common ones you'll see when browsing the aquatics department at your favorite pet store include some varieties of african catfish, corydoras, eels, freshwater shrimp, loaches, otocinclus and plecostomus.
What Does a Bottom Feeder Fish Look Like?
Even though there are several types of bottom feeder fish, this class of fish tend to have some unique adaptations you might begin to notice as you shop and keep them as pets.
These hair-like, slender appendages look like cat whiskers or spines and help the fish locate food through touch and taste, almost like long, skinny tongues.
Most species of bottom-feeder fish have a flat belly or ventral region. This allows them to hover easily and glide over the bottom surface of the tank. Some have heavy armor, or thickened areas of scales.
Bottom feeding fish have what's called "inferior" or "sucker" mouths located closer to the end of the nose and usually point down to help the pet gather food from the aquarium floor or latch onto the walls of the aquarium.
Also known as a gas bladder, this appendage helps fish regulate their buoyancy so they can stay at the bottom of the tank or swim to the top. Bottom feeders tend to have reduced swim bladders since they do not need the buoyancy. Their swim bladders also help them hear better underwater.
8 Bottom Feeder Fish Species for Your Tank
In general, bottom-feeding fish prefer sinking foods. This includes algae rounds, sinking shrimp pellets, bottom feeder tablets, dehydrated worms (tubifex, blood, white) and leftovers from their tank mates. (Although, there shouldn't be much of the latter! If there is, you're likely overfeeding your fish.) Many varieties of bottom feeders also enjoy dining on greenery in the tank, whether it's algae growth on the glass or the tender leaf edges of decorative aquatic plants. And some, well, are scavengers and will eat dead fish.
- African Catfish: African catfish from the Synodontis family are popular pets that are available in large and small sizes. Some have evolved to swim upside down so they can feed on the underside of leaves. They can be good tankmates with larger, more aggressive fish like cichlids.
- Corydoras: These cute little catfish come in over 170 varieties. One of the more common is the albino white-bodied, red-eyed cory cat. Corydoras like to graze the bottom of the tank with five or more of their own species.
- Eels: These slender, rope-shaped fish have pointy noses and come in several types. The peacock eel features yellow and brown stripes with black dots, much like the bird's tail feather pattern. Eels are shy and pair well with other docile fish.
- Freshwater shrimp: These aquarium pets come in a variety of colors and shapes, with some even being clear! Freshwater shrimp do well with multiple shrimp friends and non-aggressive fish.
- Loaches: The colorful vertical stripes of a long-bodied kuhli loach stand out in a tank. The orange and black clown loach is particularly eye-catching. Loaches get along with any docile fish.
- Otocinclus: Also known as "ottos." these fish have black-striped or two-tone tan and brown bodies. They are compatible with any other non-aggressive fish.
- Plecostomus: Some varieties of plecos are bottom feeders, including the polka-dotted bristlenose, featuring lots of barbels. Plecostomus get along with other easygoing bottom feeders.
Ready to expand your aquarium community? Learn more about which fish to add to your tank in Top 10 Best Fish and Best Beginner Fish by Tank Size.
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