If you are into freshwater fishkeeping, you might want to keep the tank varied and healthy. One of the ways to achieve it is to create an environment that synergizes and benefits each other.
Your fish tank or aquarium can have a variety of surface feeder fish, column feeder fish, and bottom feeder fish. Indeed, keeping a combination of those types of fish can help you maintain a clean and healthy environment inside the tank.
However, there is a wide array of bottom feeder fish—some of them are even predators. So, make sure you pick the right one to harmonize with other fish you have.
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What is a Bottom Feeder?
Bottom feeder fish are aquatic creatures that do not float on the surface to get food. They stay near the bottom of the water to find detritus to eat. Many of them are shy creatures, so they hide under the sand or inside holes.
Though many bottom feeder fish are considered tank-cleaners or algae-eaters, keep in mind that it does not mean that you can let the tank clean by itself. There are specific care and traits that need to be applied if you want to keep bottom feeder fish on your tank.
Traits of Bottom Feeders
Bottom feeder fish have the traits that make them different from surface feeders and column feeders. Catfish, shark, stingrays, loach, and Pleco are just some of the examples of bottom feeder fish. Check for this list of traits when you are looking at the option:
Inferior Mouth
An inferior mouth means that the mouth is located down near the bottom of the body. It evolved so that they can eat from the bottom and can still keep an eye for predators. One extreme example is the saltwater bottom feeders, stingrays, where the mouth is located on the bottom side of the body.
Barbels
Barbels are fleshy whiskers that grow around their mouth. Next time you see a catfish, check that the whiskers are more like flesh instead of hair strands. These barbels are sensitive to tastes and help bottom feeder fish to find food.
Specialized Mouth
Besides their inferior mouth, some bottom feeder fish have specialized mouths adjusting to their habitat and food. Plecos and oto cats, for example, have a mouth that looks like a suction cup.
It helps them collect food from the bottom of the water, such as algae and biofilm. In freshwater, this kind of mouth helps them to stay in place in streams.
Flat Bellies
Since they stay on the bottom, many of them have a flattened ventral region. It allows them to swim, hide, and roam around easily. These flattened bellies are not too visible in some species like koi and Cory cats, but highly noticeable on the others such as stingrays and loaches.
9 Types of Bottom Feeder for Your Fish Tank
Are you looking for the right bottom feeder fish for your tank? Learn how these species can be a great addition to your collection.
1. Botia Loaches
Botia loaches have attractive patterns on their skin. Some of them are aggressive and can grow large up to 12 inches. These types of loaches are a good addition for ponds because of their size. If you want to put it in a tank, make sure you get the right species for the size you have.
Originated from Southeast Asia, Botia loaches actively eat the scraps of the tank and love to lounge around. They usually need a school consisting of at least five fish of the same species. Although, some of them are aggressive towards other fish, especially when being kept in a small school.
Furthermore, their size ranges between 3 and 12 inches with a lifespan of up to 20 years with proper care. The tank size should not be smaller than 30 gallons with a temperature range of 75° – 85°F to maintain healthy Botia loaches.
2. Bumblebee Goby
Just like its name, Bumblebee Gobies skin resembles a bee’s stripes. These types of bottom feeder fish originated from Southeast Asia. They grow small, with adults sized only as big as 4 inches.
In their natural habitat, they like to hide between rocks and plants. So, your tank is required to have enough hiding spots for these little guys. At times, they also like to go under the substrate and hide.
However, male Bumblebee Goby can be very territorial. It might not be a good idea to put them with other territorial fish. Once put in the tank, they will claim their area and guide it from other fish.
The minimum size of the tank that is required for Bumblebee Goby is 10 gallons. Keep the temperature around 73° – 75°F to keep the environment balanced for the Bumblebee Goby school.
3. Corydoras Catfish
Corydoras are small catfish that are playful and active. They stay in schools so you might want to buy several of them. Their vibrant colors give the tank a bright addition. Corydoras are also compatible with most fish, especially if you are keeping your tank in cold water below 75°F.
The smallest school they need should consist of six fish to keep them balanced and happy. Although they are very peaceful, Corydoras can be sensitive to the environment. Avoid putting blazing sand or sharp rock to keep them out from scratching themselves.
The tank requirement they need is around 20 gallons in size with water temperature between 70° – 75°F. When treated right, they can live up to five years.
4. Dwarf Gouramis
The required living environment for the dwarf Gouramis is heavily vegetated water—just like their natural habitat in the rivers of northern India. They grow only up to 2 inches, hence the name “dwarf Gouramis”.
Male dwarf Gouramis have exotic skin colors and sometimes are a combination of orange and red with turquoise stripes. Meanwhile, females have duller colors. Still, it’s interesting to see them swim in pairs when they are placed in the same tank.
They don’t require a big aquarium because of their size. A minimum tank size of 5 gallons will do just fine as long as you keep the temperature at 72° – 82°F. Dwarf Gouramis is a very peaceful and shy fish and will live harmoniously with most species such as cichlid and tetra.
5. Kuhli Loaches
The elongated body of Kuhli loaches makes them look like eels. These creatures are good at hiding and cleaning, which will be a great bottom dweller for your fish tank. In a medium tank, Kuhli loaches or Pangio kuhlii is highly compatible with betta fish.
This type of loaches originated from Southeast Asia. Surprisingly, this peaceful creature has spines that will pop out when they feel threatened by other fish. Just like eels, Kuhli loaches do not have scales that make them susceptible to diseases and fungi.
With a lifespan of up to 10 years, they need to be placed in at least 20 gallons tank temperature at 75° – 85°F.
6. Otocinclus Catfish
Growing only at 2 inches, Otocinclus catfish are an active schooling fish that graze on detritus all day. In its natural habitat, a school of Otocinclus catfish may consist of thousands of them.
Otocinclus catfish were first found in South America around the Amazon River. They are very active and fun to watch as they go to schools. The minimum number of fish they can have in a school is ten. Make sure you get the right number to keep them happy.
However, they may take quite some time to acclimate with a new tank. It is best to add them later once you have the tank well-cycled. They live up to 5 years in a water temperature between 75° – 82°F.
7. Plecos
Originated from South America, Plecos are also known as algae-eaters. There are many species under this category. Some aquarists also consider placing Plecos for outdoor ponds as an algae cleaner. It has a suckermouth, barbels, and a flat belly—a perfect combination of bottom feeders traits.
They tend to hide in a cave during the day and find food at night. As a positive side, Plecos will not bother other species as long as other fish do not take their hiding spot. Plecos can scrape off the algae on the tank by eating it.
However, they eat a lot from algae and also produce a lot of waste. Particularly, plecos are one of the best species for committed aquarists as they live up to 15 years. They work best for large tanks around 30 – 125 gallons.
Read full Albino Bristlenose Pleco Care Guide here.
8. Synodontis Catfish
Originated from African freshwater, Synodontis is a peaceful fish that spend their time alone. There are more than 300 species of Synodontis, and many of them are compatible with cichlid tanks.
Although they are nocturnal, Synodontis may swim around to find food in the daytime. Synodontis gets along with most fish, even with African cichlids. Also, if you keep more than one Synodontis, you might want to provide plenty of caves to hide in.
With a lifespan of up to 10 years, they can grow as big as 23 inches. Prepare a tank with a capacity of 30 gallons and a water temperature of around 72° – 77°F to give the best environment for them.
9. Twig Catfish
The name of this kind of catfish derived from its unique appearance that resembles a twig. It is long and thin with a greyish pattern on its white body. It is a fun fish to play with as you will find yourself trying to find them under the substrate.
Twig catfish came from South America. They don’t swim around too much and spend most of their time motionless at the bottom of the tank. Since they are a very passive fish, they may get picked on by other fish.
Keep in mind that the tank cleanliness is a top priority to keep the twig catfish healthy. They fit in a medium-sized tank, around 20 gallons with a temperature around 75° – 79°F.
Benefits of Bottom Feeders for Your Freshwater Aquarium
Whatever size of tank you have, keeping bottom feeder fish is a good way to keep the bottom of water full of life. It creates movement and circulation. Thus, making your fish tank healthier.
However, keep in mind that bottom feeder fish do not completely clean your tank. Many of the bottom feeders require clean water and regular exchange of water. The variety of these fish characteristics proves that they can add fun for aquariums setup.
Is a Bottom Feeder Fish Right for You?
Finding the right combination of fish for aquariums might be a long journey, especially for novice aquarists. It is crucial to keep track of the water’s temperature and acidity level. For some species of fish, their lifespan and health are also determined by the plants and décor you put inside the tank.
If you have just started, you might need to go through several errors before getting the best combination. With a wide selection of varieties, find fish that can live in the same requirements and not prey on each other.
Instead of picking your favorite fish and trying to create the required environment, it is best to adjust the type of fish with your existing tank environment. Make sure that the fish do not prey on each other—to avoid tragedy in the aquarium.
It is safe to say that most aquariums need bottom feeder fish to add variety. Adjusting to your fish tank size, pick the right bottom dwellers. Through time, you will find it exciting to observe them and play hide and seek with them.