A recurring problem in aquariums is the presence of algae. In this article, we will talk a little more about brush algae. 

Brush algae

Brush algae are, to the naked eye, algae whose colors are black with blue reflections. They are also part of the red algae family. They generally grow in small tufts, not exceeding half a centimeter in height, and are quite easy to recognize.

It is also one of the longest and most difficult algae to permanently control in your aquarium. This algae attaches itself everywhere and very strongly in your aquarium, on the glass, rocks, roots, filter, heater, and even on the gravel. 

How to get rid of brush algae

Unfortunately, to get rid of this type of algae, you have to do it manually and therefore remove little by little with your hands all the small tufts that grow. It is a very long process and you will need to use a window scraper for the glass and a toothbrush with a scraper to properly clean the rocks and roots, as well as parts of your filter if they are affected. 

However, if the algae have grown on your plants, they will be lost because you cannot remove brush algae from the leaves. You must cut them and throw them away.

Precautions to prevent the appearance of brush algae 

If we cannot remove brush algae from plants, we can still prevent them from growing in the aquarium by trying to find out where the imbalance comes from. Indeed, we must remember that if algae grow in our aquarium, there must necessarily be an imbalance between the light or water parameters such as nitrates and phosphates.

High pH level

The first cause of algae appearance is often due to a high pH level. A high pH level is when the pH is between seven and nine, this will favor the appearance of brush algae. And it is often a recurring problem in goldfish aquariums and African cichlid aquariums. 

Strong agitation or strong current in the aquarium

A second cause favoring the appearance of brush algae is strong agitation and therefore, a strong current in your aquarium. This problem is very common in aquariums that have powerheads or that have a very powerful filter that agitates a lot of the aquarium water. You can also note that these algae can have the unfortunate tendency to settle on the outlet tubes of your filter since that is where there is the most current. 

So you must remember that the appearance of algae in your aquarium means that there is an imbalance somewhere and that you must therefore test the water of your aquarium in order to identify the cause and treat this imbalance.

Clean the decor and call on the helpers

Brush algae tufts attach strongly to the decor. To clean it, remove it from the aquarium and soak it in hot water, without any household products. Rub it gently with a new toothbrush or a clean sponge, let it cool, then rinse it with aquarium water before putting it back in place.

Some animals graze on brush algae and help contain them, without solving the cause: the Crossocheilus (Siamese algae eater), the Amano shrimp (Caridina multidentata), the Otocinclus or the Ancistrus. Choose species adapted to the volume and population of your aquarium.

On the settings side, limit the lighting to about 8 hours a day, avoid direct sunlight and change the water regularly. If your water is very hard, a cut with reverse osmosis water helps lower the carbonate hardness.

What elements to test and how to eliminate them? 

The first element you must test: nitrates.

If you have too many nitrates in your water, that will mean that you haven't done enough water changes or that your filter is not powerful enough for the organic load, in other words, you may have too many fish. Indeed, overpopulation of fish can often be the cause of algae problems in the aquarium. 

The second element to test: phosphates. 

Phosphates are always present in our water and plants need them for their growth. It is therefore not an element that needs to be at zero milligrams per liter. It is important to have a little phosphate at a regulated level. And it is also important to have a balance between nitrates and phosphates. Ideally, you should have ten milligrams of nitrates for one milligram of phosphates. If, for example, you have nitrates at 20, which can happen, you should have two milligrams of phosphates. You will therefore need to pay close attention to this nitrate-phosphate balance. In addition, if you have too many phosphates in the water of your aquarium, you will favor the growth of algae at the expense of plants. 

Nitrates are easily eliminated, you just need to do water changes and they will be automatically eliminated. You can thus easily fall back on an adequate nitrate level. 

For phosphates on the other hand, it is a little more complicated because most of the time, when we have a water problem, it is often due to the fact that the tap water is already loaded with phosphates. So, there is no need to change the water for this type of problem. 

So to eliminate phosphates from the water of your aquarium, you will have to use anti-phosphate resins. Anti-phosphate resins are a mass of filtration in small beads to put in your filter and which will then neutralize the phosphates. 

If despite the reduction of nitrates and phosphates, brush algae still persist and grow, at that point, you must test the iron. Iron is like phosphate, you need some in the water of your aquarium since plants need it to grow.

If you have an iron deficiency, the plants will tend to turn yellow. But if you have too much iron, it is the algae that will take advantage of it at the expense of the plants. The ideal iron level in the water of your aquarium should be between 0.05 milligrams per liter and 0.1 milligrams per liter only. If you have a few tufts of brush algae that start to appear here and there on your decor and on your glass, you must remove them immediately and of course, test your water. 

Small tip to limit the appearance of algae in your aquarium: do not hesitate to add fast-growing plants. These plants will capture nutrients faster than algae can. So they will be able to counteract the appearance of algae.