Although it’s important to keep in mind that no fish is ever going to fully fix an algae problem and manual cleaning will always be necessary, it can still be a great idea to go for an algae eating species to help you out with this task. If your aquarium set-up is suitable for them, they make great additions that are fun to keep and will do the best they can to devour algae.
Keep reading for a list of the best algae eaters!
Note: you can find a guide on green algae causes & removal here.
Amano shrimp (Caridina multidentata)
Amano shrimp are at the top of this list for good reason. Although not actually a fish, they are considered by many to be the ultimate algae eater for the aquarium. They spend most of the day searching for food and grazing on many types of algae, can be kept in smaller aquariums of at least 10 gallons (38L) and are entirely peaceful. A group of at least five in an aquarium with similarly peaceful tankmates can be very effective in helping you deal with an algae problem or preventing it before it happens.
They will also gladly eat all kinds of fish food, making them effective as a cleaning crew so no leftover foods will start rotting and possibly polluting the water.
Twig catfish (Farlowella vittata, also sometimes Farlowella acus)
Unlike most of their whiptail cousins, which have an appetite for worms and other small creatures, Farlowella vittata is herbivorous and prefers green and brown algae along with a varied diet of blanched fresh vegetables and algae wafers. Like Amano shrimp, they’re a very peaceful species that will thrive in a calm planted community aquarium. A tank size of at least 30 gallons (115L) is preferred, plenty of driftwood to “hide” on appreciated.
Keep a close eye on your water values at all times and be sure not to introduce these catfish to new aquariums that are still at risk of experiencing cycle bumps; they are very sensitive and won’t react well to bad or fluctuating water quality!
Otocinclus catfish (Otocinclus affinis, macrospilus, vittatus)
Otocinclus are a small, timid catfish species that prefers to be kept in groups of at least 6 with other peaceful community fish in order to feel safe.
Due to their size, these catfish don’t require a large setup; 10 gallons (38L) is a great place to start for a group. Like twig catfish, they are very sensitive to bad water quality and mortality rates during shipping and after being introduced to the aquarium are quite high. Be sure to buy from a responsible seller and keep a very close eye on your water values!
Healthy Otocinclus can regularly be seen scraping algae from leaves, rocks and tank walls and although they won’t eat all types, a group of these fish can really help with algae control. You can supplement their diet with fresh vegetables, which they will really appreciate, and algae eater foods.
You can find a full Otocinclus caresheet on Aquariadise here.
Siamese algae eater (Crossocheilus siamensis)
The Siamese algae eater naturally occurs in fast flowing streams and rivers and is well known for its appetite for black beard algae, a type of algae almost no other fish or invertebrate is interested in.
Although they’re not the most suitable fish for a small setup because they can grow to a size of up to 6 inches (15 cm), a rectangular aquarium of at least around 80 gallons (300L) should be enough to house a group. 6 or more fish is preferable! A hillstream type setup that imitates the natural habitat works best for these fish, although they are generally peaceful and will do well in ‘regular’ aquariums as well.
When buying Siamese algae eaters, don’t just go by the common name on the label in your aquarium store. There is another fish species sometimes sold as Siamese/Chinese algae eater, Gyrinocheilus aymonieri, which gets quite aggressive and stops eating algae as it ages. There is a lot of confusion about the species names within the Crossocheilus genus as well and not all species are equally effective at eating algae, so if you’re really going for an algae cleaner you may want to do some extra research.
More information about the species names can be found here!
Nerite snail, Neritina sp., Clithon sp., etc.
There are many types of nerite snails available in the freshwater aquarium trade that all have beautiful patterns and are known for being great algae eaters. Due to their size (they’re the smallest creature on this list!) they make a suitable cleaning crew for almost any size of aquarium.
Contrary to other snail species, like pond snails, Nerites only reproduce in brackish waters and will therefore never overrun your tank and turn your algae problem into a snail problem. They are also completely peaceful, which means they do well with even the smallest tankmates like shrimp fry. However, like all snails they won’t do well in soft water – they need hard water to prevent deterioration of the shell and eventually death.
If your nerites run out of algae you can switch to an algae pellet or shrimp food that contains plenty of veggie matter and algae. The video below clearly shows how effective these little guys are at devouring algae, so you may have to switch to an alternative food sooner than you’d expect!
You can buy nerite snails online here!
Keep in mind…
Please keep in mind that it’s definitely not a good idea to buy an algae eating species just to deal with algae. They can’t just be tossed into any aquarium, need specific care you have to be willing to give and will unfortunately never replace manual tank maintenance.
If you have any more questions about algae eaters and which are suitable for your aquarium or if you want to share your experience with one of these species, leave a comment below!