Black beard algae is one of the harder types of algae growth to control in your freshwater tank.
Very few fish will eat it – even among fish that eat algae. But there are a few that will eat it.
The best black beard algae eaters are siamese algae eaters, florida flag fish, golden algae eaters, chinese algae eaters, flying foxes, goodeids, and rubber lip plecos. Though they aren’t fish, nerite snails and amano shrimp will also eat black beard or black brush algae.
Let’s go into a bit more detail.
Siamese Algae Eaters
Siamese algae eaters are probably the best known and most widely recommended fish for eating black beard algae.
These guys are definitely my first choice as well, as long as you have a 30+ gallon tank that’s at least 3′ long.
When SAE are young, they will absolutely destroy most of the types of algae that other fish won’t touch, including hair algae. (They may also eat certain aquarium plants, like mosses.) As they grow older, however, they’ll slowly stop eating algae and will start focusing on more normal sources of food.
Sad, but it’s a tradeoff you need to be willing to take if you want their services when they’re young.
Florida Flag Fish
The Florida Flag Fish, also known as the American Flag Fish is a less common fish in the hobby, but it is one of the few that will eat black beard algae.
Like other killifish, it can be demanding in its level of care, however, so I wouldn’t buy it just to get rid of algae.
If you’re looking to add a killifish to your tank anyway, however, this fish is willing to help you out with your BBA problem.
And as an added bonus, some types of FFF look quite lovely.
Chinese Algae Eaters
Chinese algae eaters are a pretty controversial choice, mainly because they get large (around a foot long) and aggressive with age.
When they’re young, they’re relatively peaceful, but as they get older, they’ll start getting more aggressive and latching onto other fish.
They’re the cheapest type of algae eater I’ve found, however, so it may be a viable strategy to buy one to take care of an algae problem and then drop it off at the fish store again when it starts getting big.
It also could be a viable option if you already have a tank full of fish that get large and aggressive.
Flying foxes are a fish that is often confused with the Siamese Algae Eater, and it will often be sold as an SAE.
They aren’t as good as the SAE at eating algae, but they will often eat both black beard algae and hair algae. (It’s hit or miss depending on the individual fish.)
They also can be a bit more aggressive than the regular SAE, so that’s something else to watch out for.
They get a bad rap, but they’re a fish that might be worth considering.
Rubber Lip Plecos
Rubber Lip Plecos, also called bulldog plecos, are perhaps the hardest working member of the pleco family.
Whereas there is often a debate as to whether or not some species of pleco really even eat much algae, the rubber lip pleco is an algae eating machine.
It’s (to the best of my knowledge) the only type of pleco that will eat black beard algae, and it stays small, so it’s good for tanks 25 gallons and up.
The downside to them is they’re not much to look at. (Honestly, I think they’re one of the ugliest plecos, but they make up for it in their usefulness.)
If you’re looking for a pleco to add to your cleanup crew, this is the species that gets my recommendation.
Nerite snails are one of the most popular snails for freshwater aquariums, partially because of the fact that they eat most types of algae (including hair algae and BBA).
If they like the conditions in your aquarium, they’ll drive around your tank all day eating algae, dead plant matter, and leftover fish food.
(If they don’t like the conditions in your tank, they’ll leave, and you’ll find them on the floor.)
They’re also cheap and very easy to find – being sold most places that sell fish at all. Their shells come in a few different colors, from a drab brown to yellow and black striped, and other colors and patterns in between.
The downside to nerites, other than their propensity for escaping, is that they’ll leave eggs all over your aquarium. (They won’t hatch, but if you want them to go away you have to scrape them off.)
Amano shrimp are another one of the best algae eaters for your aquarium.
If your water parameters are right for their survival, a good sized population of amano shrimp can decimate an algae problem in your aquarium.
The downside is, of course, that they can be somewhat expensive and don’t reproduce in a freshwater aquarium.
If you don’t mind shelling out the money for them, however, they’ll eat most types of algae, including black beard algae (though it will probably be the last type of algae they eat, as it’s not very palatable).
Algae eating aside, amano shrimp are great to keep in your aquarium just because you want shrimp. They don’t come in a bright, eye catching color, but they’re one of the less finicky types of shrimp, so they can survive where others might not be able to.
Goodeids are a relatively unknown family of fish in the fishkeeping world, but a lot of members of the goodeid family will eat black beard algae.
A few that are supposed to be particularly good at eating black beard algae are Ameca splendens, also known as the butterfly splitfin, and xenotoca eiseni, also known as the red-tail splitfin. The rainbow goodeid, Characodon lateralis, is also another potential option that might eat black beard algae.
It’s important to know that some members of the goodeid family are mostly carnivorous, so you should evaluate the type you’re getting before you buy it thinking it will eat BBA.
It’s also important to point out that some of them can be nippy and may not make the best addition to peaceful community aquariums. Some may also damage sensitive aquarium plants.
Here is a forum thread where you can learn some more about these fish.
Getting Rid of Black Beard Algae
As you can see, not many species of fish are well suited to eating BBA, and those that are often can’t be added to an aquarium for other reasons. Amano shrimp, nerite snails, and rubber lip plecos are probably the best all around options for control of BBA and other algae growth.
Still, the best method for controlling black beard algae may be making systematic changes in your fish tank. Here are a few:
- Change your water and gravel vac to reduce the level of organic matter in your water column. (Weekly water changes may help until you can get things under control, then regular testing of your aquarium water parameters afterwards.)
- Add a product like purigen to futher remove organic waste from the tank water.
- Reduce the amount and/or duration of light you’re providing your aquarium. (Through aquarium lights and sunlight that may be hitting your tank.)
- Provide carbon to your plants either with a dedicated CO2 setup or using a liquid carbon product like Seachem Excel.
I’d also note that phosphate levels, while correlated with BBA growth, aren’t necessarily the cause of it. High phosphate levels may be caused by other imbalances in your aquarium – like CO2 for instance – that prevent your plants from taking up the nutrients in your water column.
These steps, combined with adding a few algae eaters into your tank should help you reduce the amount of black brush algae you see in your fish tank.