Home | Aquarium Livestock | Algae Eaters and Plecos for Small Freshwater Aquariums

Algae Eaters and Plecos for Small Freshwater Aquariums

Finding the perfect new addition to an aquarium is often like finding the Holy Grail to many aquarists. We all want the perfect little helper to keep the tank clean so there’s less work for us to do (and so our tank is cleaner and healthier, of course) but many “algae eaters” get too large for smaller aquariums and many others like the group of fish known as “plecos” don’t even eat algae at all. So what are the best plecos and algae eaters for small freshwater aquariums? Here are a few of our favorites that are some of the best choices for smaller community aquariums:


Bushynose & Bristlenose Plecos (genus Ancistrus)

Starlight Bristlenose Pleco (Ancistrus dolichopterus L183)

Starlight Bristlenose Pleco (Ancistrus dolichopterus L183)

  • PROS: Lots of variety in color and pattern, small size, vegetation-heavy diet (including algae), community-friendly.
  • CONS: Some species grow larger than others, needs meaty foods as well, underfed fish may eat live plants.
  • BEST SUITED AS: A community algae-eater and bottom-feeder.


Plecos from the genus Ancistrus usually have “Bristlenose” or “Bushynose” somewhere in their common names, a nickname that comes from the whisker-like frills that develop on most adults. They are usually more prominent in adult males but some females may get them too in some species. Different species in this group have different requirements, but they are generally among the smallest plecos. While they eat some meatier foods as well, most appear to eat mostly vegetation.



Clown Pleco (Panaque maccus L104)

Clown Pleco (Panaque maccus L104)

Clown Pleco (Panaque maccus L104)

  • PROS: Small size, easy-going temperament, fairly wide-spread diet.
  • CONS: Need driftwood for grazing, not primarily an algae-eater.
  • BEST SUITED AS: A general clean-up bottom-feeder for community aquariums.

The Clown Pleco is a popular small pleco. As with other Panaque plecos, these fish are omnivores and feed about equally on plants matter and meatier foods. Panaque plecos are also unique in that they actually feed on driftwood as well; make sure you have driftwood décor in your tank for these fish to graze on.




Hillstream Loaches

Reticulated Hillstream Sucker (Sewellia lineolata)

Reticulated Hillstream Sucker (Sewellia lineolata)

  • PROS: Eats algae, can be kept in groups, unique and unusual appearance.
  • CONS: Needs high flow and pristine water, vulnerable to aggressive tankmates and poor water chemistry.
  • BEST SUITED AS: A unique addition to a suitable community aquarium where it incidentally may help eat algae but isn’t the primary algae-eater.

Hillstream Loaches have flattened guitar-shaped bodies and are often mistaken for plecos. They cling to rocks in the fast-moving mountain stream where they come from much like plecos cling to surfaces. Hillstream Loaches need well-oxygenated and well-filtered tanks and don’t do well with nippy tankmates or in tank with less-than-pristine water quality. They do eat some algae however, as well as other detritus and leftover sinking foods.



Otocinclus Catfish

Dwarf Suckermouth Catfish (Otocinclus sp.)

Dwarf Suckermouth Catfish (Otocinclus sp.)

  • PROS: Small size, safe for planted tanks, primarily algae-eaters.
  • CONS: Can be sensitive to stress, can starve if they can’t find enough to eat.
  • BEST SUITED AS: Algae-eating housekeepers in planted community aquariums.


There are a few very similar species that are commonly grouped together as Otocinclus Catfish (“Oto Cats”) or “Dwarf Suckermouth Catfish”. Most are brownish-grey in color with a black stripe but some like the Zebra Oto (Otocinclus cocama) have a more ornate pattern. These fish stay under two inches in length and are great for eating algae off of plants without harming the plants. They can be a bit finicky and sensitive though so only keep in a stable, healthy aquarium. They are also best kept in groups so plan tankspace accordingly.



Rubbernose Plecos (Chaetostoma sp.)

Spotted Rubbernose Pleco (Chaetostoma sp.)

Spotted Rubbernose Pleco (Chaetostoma sp.)

  • PROS: Moderately small adult size, eats some algae, community temperament.
  • CONS: Not a primary algae-eater, can be bulky for very small tanks.
  • BEST SUITED AS: A general bottom-feeder for community tanks over about 30-45 gallons.


Like the Clown Pleco, Rubbernose Plecos are some of the most common smaller plecos available. They also have a very familiar pleco-like appearance that many novice aquarists associate with algae control. They are not exclusive algae-eaters however; this is another omnivore that needs about equal parts meaty food and plant matter. These fish are pretty middle-of-the-road overall: moderate adult sizes, eats diet for about half their diet, neutral coloration, moderate temperament.



Freshwater Nerite Snails

Freshwater Nerite Snails (Neritina sp.)

Freshwater Nerite Snails (Neritina sp.)

  • PROS: Colorful shells, safe for plants, small size.
  • CONS: Limited availability, may reproduce, may be vulnerable to predators.
  • BEST SUITED AS: Algae-eating grazers for small planted aquariums.


Nerite Snails are popular for saltwater aquariums but some species are found in freshwater as well. These snails are much smaller than some of the other less-suitable and more invasive freshwater snails like Apple Snails or Trapdoor Snails. They mainly eat smaller algaes like the ones that cause spots on glass but usually won’t harm plants. These snails also appear to bred less frequently in most aquariums than the more common Apple Snails. Make sure the ones you get are from freshwater; a saltwater Nerite will not survive being moved to a freshwater tank.


Freshwater Shrimp (Caridina sp.)

Several freshwater shrimp (Caridina sp.)

Several freshwater shrimp (Caridina sp.)

  • PROS: Safe for plants, small size, can be kept in groups.
  • CONS: Limited availability, vulnerable to predators, very small.
  • BEST SUITED AS: Algae-eaters for planted nano tanks with peaceful or no other tankmates.

Small freshwater shrimp like the popular Cherry Shrimp and Amano Shrimp can be ideal grazers, especially for nano tanks (under 1-2 gallons). Some are clear, some are colored or have colored markings and they can be kept in groups. However, most of these shrimp are very small; you may not see them often and can’t be kept with anything remotely predatory.      




As always, the best algae-eater for your tank depends on its tankmates, the size of the tank, the water parameters and other such factors but hopefully this helps give you some alternatives to fish that may be too big or otherwise unsuitable to your needs. If you need more help in making your best choice or have a favorite of your own, feel free to comment below!


  1. avatar

    I have an Ivy plant in a medium-small glass vase which keeps growing algae and I was wondering if there were any Algae eaters that could live in these conditions.


  2. avatar

    Hello e, That would depend on what type of Ivy it is for starters…some can be toxic to aquatic animals. In general though, there are really no algae-eaters that do well in an unfiltered, unheated vase. You could try a snail like the freshwater Nerites in this blog or a few of the small nuisance snails common in freshwater planted aquariums (ask any friends with freshwater planted tanks or check with your local fish stores that have freshwater plants…they will likely have a few to spare for you).

  3. avatar

    Nerite snails are probably the worst possible choice for control of algae in a vase, as they will quickly leave water that is not suitable to their liking, and obviously die given no other options. You can use Pond Snails, which are sometimes considered pest snails in display tanks, but are also embraced by many for their strict diet of algae, quick reproduction, and ability to survive pretty much any water conditions, including dirty stagnant water. Another option is to use an algae killing chemical, of which there are many for ponds and aquarium. Removing the plant if possible would allow for dips in hydrogen peroxide. If not, buy Flourish Excel and dose triple strength until algae discolors, which means its dead. This last option will likely stimulate growth of your ivy as well.

  4. avatar

    Hello Steven, I would agree that Nerite Snails wouldn’t be appropriate for a bowl; this information here is mainly for filtered (and heated, when applicable) aquariums. For bowls like Betta bowls, I wouldn’t actually recommend any of these fish or inverts since they are all generally tropical and need consistent temperatures, water quality and filtration. For bowls, I would recommend regular maintenance and water changes over a cleanup animal that most bowls cant safely handle.

  5. avatar

    I have a small 2.77 gallon tank with fake plants that house one fighting fish ( betta) and two guppies. What kind of algae eaters would be best for my tank?

  6. avatar

    Hi Lori, I really wouldn’t recommend any additional algae-eaters for that tank given its size and what is already in it. Bettas usually don’t tolerate any other tankmates at all and behavior aside, those three fish alone would max out the occupancy of the tank when full grown. If you would really like to try out an additional cleaner beyond regular maintenance, I wouldn’t do anything more than a Nerite Snail or two.

  7. avatar

    True ramshorn snails, the ones many aquarists see as pests because they will eat the leaves of certain live plants, such a lilies, would be fine for the set up if there is in fact algae. You could easily get 2 for free from most any pet store that sells live plants, as they often hitchhike in with the plants. You can go on amazon and order really nice blood red strains if you are willing to spend the money, or just settle for the black/grey/brown ones that are free. As long as you have 2 they will breed and they’re population size will be limited by how much they have to eat, which should be very little. They will eat any left over flakes that are uneaten, but if you find you are feeding extra for them then you have increased your already high bioload and the fish will die. Don’t be fooled into paying for giant ramshorn snails, which is a snail that is sometimes sold for ponds and large fishtanks and gets massive. The snail im talking about should be no larger than a quarter inch, maybe a little more. https://en.wikipedia.org/wiki/Ramshorn_snail

  8. avatar

    It is true that some Ramshorn Snails may be good algae eaters but be careful…some species are considered invasive and are illegal to buy, sell or transport. We do not sell them here and are under instruction by our local authorities in Pennsylvania to immediately dispose of any that are found on our plants.

  9. avatar

    I am looking for an algae eater that will fit in a 10 gallon tank. I only need it for like 3 months so size doesn’t matter in that sense. Any suggestions?

  10. avatar

    Hello SMK, I would recommend the algae eaters listed here in this blog. They are all species that would be appropriate for your size.

  11. avatar

    I keep buying algie eaters at walmart and they keep dying..i have a 10 gal tank..have 3 zebra fish,a white shark, a gold colored fish and a newbie from walmart thts making it so far…the tank has rocks, plastic plant, and a mushroom type item where they can go in and out….the tank is organgie looking and getting black on the windows, i was told to leave the light on all day and turn off at night…nothing is working and the algie is getting worse..when i do fill up with tap water, i add per directions the stress coat liquid..wht am i doing wrong??? I ♡ my fish !!

  12. avatar

    Hello MB, I would need more information about your tank to help you diagnose the problem. Just like when they take your pulse and blood pressure at the doctor’s office, getting the “vital signs” is important…in the case of aquariums, that comes to water testing. Have you tested your water, and what are the values for pH, Ammonia, Nitrite and Nitrate especially? Given the “black” that you are mentioning, I would test phosphate levels as well. Also, how long has the tank been set up and established? Do you have a heater in it and what temperature is it at? What type of filter do you have on the tank and what type of maintenance have you been doing (water changes, how much and how often, filter media changes, etc.)? Knowing what type of fish you have and how large they are would be helpful too to make sure that everything is compatible. It sounds like you may have a couple different issues going on but I can’t say for sure without more info. I would recommend getting that info together and giving us a call at 717-299-5691 so we can diagnose the issue better and get a gameplan together with you to get your tank back in shape.

  13. avatar

    I have a small aquarium I bought from Walmart and it has two goldfish,rocks, artificial plants and a pump and filter. What would be the best algae eater for my tank?

  14. avatar

    Hello Tammy, How “small” is this tank? Two goldfish should have at the very least a 20-30 gallon tank even when small to handle the waste they produce. If your tank is any smaller, I would not recommend adding anything else to it. If the tank is over that size, snails would be your best bet since other algae-eaters like those discussed here are tropical fish and would need warmer water than goldfish.

  15. avatar

    I currently have 3 zebra danio and 4 glo danio in a 5 gallon tank… I am looking to eventually add 3 small tetra… would the Amano or cherry shrimp be ok in that environment??? I have no live plants…

  16. avatar

    Hello Mommyof2, The fish you already have in that tank are already a lot for a tank that small. I wouldn’t recommend adding anything else to the tank. A couple shrimp may be OK with what is already in there but as it is already fully stocked, the water quality may not be up to what the shrimp would need.

  17. avatar

    I have a 5g hexagon tank w/ 3 small glo tetras and a small aquatic frog (very basic plastic decoration, good filter, heater & air bubble wand, and I am diligent about cleaning & treating it weekly). I had a small pleco (knowing eventually i need to upgrade the tank size) and a couple small tiger barbs as well. The tank kept developing the white hair fungus – I’m assuming because the pleco and frog weren’t eating the bottom feeder pellets and so they kept dissolving into the gravel and building up despite me vacuuming the rocks. Unfortunately i lost my pleco and 2 barbs last night and panicked that my other little guys would perish. I removed them, cleaned out my tank, set it back up and when it was treated and good temperature, placed my 3 tetras and frog back in today. They seem fine so far. I know I’m basically at capacity, so I prob would only add 1 or 2 more glo tetras at most for schooling purposes, but I still want to add 1 small algae eater. From what I’ve researched, a bristlenose pleco, oto catfish, loach or small snail would be best for my tank. Also I’m not completely opposed to adding a small live plant. Given everything I’ve mentioned, what would you recommend?

  18. avatar

    Hello Kris, I wouldn’t recommend any more fish for that tank…it is already pretty crowded. A small snail like a freshwater Nerite Snail would be your safest choice.

  19. avatar

    Hi there. I have a corner 55 gallon, and I currently have 2 gold skirt tetras, 2 male blonde delta guppies, and a red wag platy. This is my first tank since I had this tank set up for my goldfish, Prometheus, and Koi, Amadeus, who have since been moved to a pond. I don’t have much experience with the tropical fish, but these guys seem to be doing okay after 4 months. I do not have live plants yet, as I’ve never had more than the one Prometheus ate when she was only a year old, that was 7-8 years ago. Lol. I am looking for a good cleaner for my tank, as it gets quite a bit of sun, and therefore algae. My house is very open with lots of windows. It was pretty difficult finding a place to even have the tank where it wasn’t against a window. I hope to add maybe a couple more guppies, and another platy to my tank in addition to a pleco or similar helper. I don’t want to over stock it, but it seems like a lot of tank for 5 small fish. 🙂 what would be a good, fairly hardy option for me?

  20. avatar

    Hi Kayla, Any of the algae eaters in this blog would still be suitable choices for your tank. I would stay with a smaller algae eater like these plecos but you could get more than one of them or get a pleco like the Ancistrus plecos and some snails like the freshwater Nerites. A small school of the Otocinclus would do well also. You have pretty many options with your size, especially since it isn’t crowded.

  21. avatar

    I have a 10 gallon with 2 goldfish in it. I can’t seem to keep the algea under control. The tank gets almost no direct sunlight. Anyone have any suggestions?

  22. avatar

    Hello Todd, A 10-gallon tank is very small – too small, really – for goldfish and keeping that tank clean will be nearly impossible. Fancy goldfish should have at least a very heavily-filtered 30-gallon tank and common goldfish will need much larger. I can’t recommend putting anything else in that tank and would recommend upgrading the tank size. Goldfish are coldwater fish as well and the recommendations in this blog entry are tropical (warm water). You likely have a water quality issues that is feeding the algae and it won’t go away until that is addressed. Have you tested the water quality, and what are the values for pH, Ammonia, Nitrite, Nitrate and Phosphate to start with? Is the water itself green or is the algae on the surfaces inside the tank? Knowing more about the tank will help us address the issue.

  23. avatar

    Just saw the reply, thank you! I am going to pass on snails, as the hood for my tank was lost in the move while it was empty (hello adding water every other day!) I should also mention I don’t have it heated. Though with so much sun, it is usually around 72 during the day, and 68/70 at night. In the winter it sits around 68 day and night. The algae has also been insane with the longer days, I clean the glass and ornaments about 3x a week, so I need to get to the store and get some little helpers! Thanks again!

  24. avatar

    Hi Kayla, Happy to help. I would recommend heating that tank though. The fish that you have in it are tropical and will do much better in a warmer tank with consistent temperatures. They should have water temperatures that are consistently between about 76-82 degrees. Cooler temps may actually be contributing to your algae issues since some nuisance “algae” thrives in cooler temps, and the cooler temps leave your fish vulnerable to diseases and parasites like the dreaded Ich. Good luck!

  25. avatar

    Okay, I’ll look into getting a heater too. They all seem pretty active and healthy, but obviously I want them to stay that way! And of it helps with algae, I’m in! 🙂 just wish I could find a darn hood. Hopefully my fiancé can fan something from plexi glass, to help hold the water in, as it evaporates SO quickly in out house. I add 3 gallons almost every other day, so at least other than when I clean the gravel, I don’t have to worry too much about water changes! I also have 2 filters in it, like I said, I had a very large goldfish (about 7″ long and 3.5″ high) plus a koi almost that big in there before they went to a pond, so I already had a good filtration system. Probably more than I need for 5 little fish in 55 gallons. Haha

  26. avatar

    Kayla – Keep in mind that waste doesn’t evaporate so adding water for evaporation shouldn’t replace regular water changes! If you need help finding a lid, feel free to give us a call at 1-888-THAT-PET and we might be able to order one for you if we don’t have anything in stock. Canopies sell out pretty quickly when we are able to get them in but we are usually able to get most standard sizes. A 55-gallon corner tank is a bit of an oddball but we may have something that would work for you.

  27. avatar

    I do still clean the gravel, which includes a water change, but I am also used to very frequent water changes, having had goldfish and Koi for all of my previous tanks, and still having them in a pond, and in our horses water trough. I will check that out, I have been looking for about a year for one, and haven’t been able to find one. Thanks again for all your help!

  28. avatar

    Hi! I am going to get a 75 gallon tank with 2 or 3 bluegills and a rubbernose pleco, also having different varieties of snails and a small school of crappie minnows. Would two flower/wood shrimp and two ghost/glass shrimp be okay with the bluegills/sunnies? I will have live plants, driftwood and a fake natural looking fish hideout in the tank. Will also have a HOB filter with a sponge. Thanks!

  29. avatar

    Hi Emma, Your Bluegills would likely eat any shrimp you added to that tank. Depending on their size, they may eventually eat those minnows as well. I wouldn’t recommend adding anything else to that tank and especially not small crustaceans. If it helps you, we do have another blog entry on Sunfish Care – Keeping Pumpkinseeds, Bluegills and Their Relatives.

  30. avatar

    I was thinking of having the sunfish as babies and once they get too long releasing them back to the pond where I would get them from if they wouldn’t get along with the shrimp as adults. I would do that each time they grew too large. Would that work? Or should I just drop the shrimp idea? I have read your sunfish page and skimmed through it a few times, but I’ll read it again. I love doing research on animals!

  31. avatar

    Hi Emma, I still would not attempt shrimp with the Sunfish since Sunfish naturally eat crustaceans like shrimp. Taking any fish out of their natural environment, keeping them in an aquarium and re-releasing them is always a risk and is against the law in some areas. I would recommend contacting your local fish and game commission to make sure that what you would like to do doesn’t violate any regulations in your area.

  32. avatar

    Thanks! I’ll look into it. You have helped me a lot and I’m very grateful.

  33. avatar

    You’re welcome, Emma. Good luck!

  34. avatar

    Hi! I have a 36 gal tank with a large veiltail goldfish,a large what I think is a marbled angelfish, and a new bala shark fish. I have had the tank for about 3 months, it is an upgrade from a 10 gal that I had about for about a year. The angelfish was the size of a silver dollar when I got it and now it is as big as my palm. My problem is my plecos..I’ve had I think 3 die recently. I don’t understand why?! All my other fish appear to be healthy. I don’t know if I want to keep trying with them. Is there anything that I can get to help keep the tank clean that is maybe more hardy and can live with the types of fish that I have? Thank you in advance!

  35. avatar

    Hi Carly, That is a difficult question to answer. Goldfish are a coldwater fish that are not compatible with warmwater tropical fish like Angelfish and plecos. They also produce a lot of waste that can affect water quality and a 36-gallon tank with a large goldfish is on the small side. It is also on the small side for an adult angelfish since they are sensitive to water quality and can get very aggressive and territorial. Bala Sharks get very large and a 36-gallon tank is certainly going to be much too small for that fish. Without knowing more about your water quality – pH, Ammonia, Nitrite, Nitrate, and temperature to start with – I can’t say why the plecos aren’t doing well in the tank but that may certainly be an issue. I wouldn’t recommend adding anything else to the tank with the fish you already have but if you would like to send me some more information about the tank like the water parameters I’ve mentioned, how often you do water changes, how often and what types of food you feed, I’d be happy to help you figure out the best path from here. You can also give our Fish Room staff a call at 717-299-5691 to discuss your tank.

  36. avatar

    I have a micro tank with 2 male fancy guppies. I have notice the water is already getting murky and the fish have only been in it a day or to. i was wondering if there is a good “cleaner” fish to accompany these fresh water guppies, something that eats algae and balances the PH of the habitat.

  37. avatar

    Hello Jessica, No fish is going to balance pH. In fact, if the tank is too small, adding more animals to it is going to just make the water quality worse. How small is this “micro tank” and what kind of filtration do you have on it? Any new tank will also go through a cycling process in which some cloudy conditions and poor water quality spikes are normal, especially if the tank is too small, underfiltered or overcrowded. You can read more about this on the Explaining the Nitrogen Cycle article on our website. If your tank is very new, it is also not likely algae that you are seeing so it is likely far too early to be adding an algae eater. More information about the tank – size, filtration, current levels of Ammonia, Nitrite, Nitrate and pH to start with – would be helpful to recommend what would be best for your tank.

  38. avatar

    its aprox 2 gallons and is a basic children’s set up. no filtration as the set was a gift to my young niece, it is quite small and uncovered. it is for all intensive purposes a fish bowl not really a tank. im not sure if a filter would fit properly in it.

  39. avatar

    Hi Jessica, Guppies are tropical fish that need consistently warm temperatures and pristine water conditions to do well. Without a filter and heater, it is going to be very difficult to keep them healthy in that tank for long. That type of tank is much more suited to a fish like a betta that doesn’t need a filter and can handle the unfiltered conditions (but it will still need to be somewhere where the temperature remains fairly consistent without a heater to maintain it). I can’t recommend adding anything else to that tank.

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About Eileen Daub

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Marine Biologist/Aquatic Husbandry Manager I was one of those kids who said "I want to be a marine biologist when I grow up!"....except then I actually became one. After a brief time at the United States Coast Guard Academy, I graduated from Coastal Carolina University in Myrtle Beach, South Carolina in 2004. Since then, I've been a marine biologist at That Fish Place - That Pet Place, along with a Fish Room supervisor, copywriter, livestock inventory controller, livestock mail-order supervisor and other duties here and there. I also spent eight seasons as a professional actress with the Pennsylvania Renaissance Faire and in other local roles. If that isn't bad enough, I'm a proud Crazy Hockey Fan (go Flyers and go Hershey Bears!).