How to Fight 6 Types of Algae in Your Fish Tank

Algae are plant-like organisms that occur naturally in a freshwater tank. There is a wide range of algae, but you are likely to encounter some of the more common types of Aquarium algae.

The processes that help and support algae growth are the same that help plants to grow. Plants and algae contain chlorophyll and create their nutrients through photosynthesis, meaning they convert light and organic matter in the water into new growth.

Fish waste and uneaten decayed food in the tank can provide a rich source of nutrients for algae. Let’s look at 6 of the most common types of algae and how to fight them.

Brown Diatom Algae

Diatom algae are one of the simplest algae to remove. It is so soft that it easily rubs off with an algae scrubber sponge. It is a flour-like substance with a dusty appearance (sometimes green in color) enveloping your aquarium substrate and walls.

Many critters such as otocinchus catfish, shrimps and snails love to feed on it. Diatom algae are often a result of high amounts of silicates and phosphates that the plants will eventually consume when given time.

Black Beard Algae (BBA)

As its name implies, BBA grows in very thick clumps. They are black, but can sometimes appear in shades of a red or brownish color. BBA can be quite problematic to run into because not many things feed on it. It can completely permeate an aquarium in a couple of years if left unchecked.

BBA likes to grow on your aquarium décor or plants. There is no one simple way to treat it since a lot of things contribute to its growth. This type of algae can take six to eight months to get established, and almost at least the same length of time to see the end of it. To get rid of BBA naturally, consider introducing Amano shrimp, Florida flag fish, or Siamese algae eaters.

For the shrimp to have some impact, you need to have quite a number of them because they take a long time to eat the algae. Another option you can turn to is chemical treatment such as utilizing liquid carbon.

This is sprayed directly on the BBA for tough cases. For mild cases, you can dose the entire aquarium water column. But, be cautious because certain plants like Vallisneria don’t react well to liquid carbon.

An alternative chemical that can be sprayed on BBA-infected plants or decor is hydrogen peroxide (3%). This can be found at your local drugstore. Spray the plant or decor outside of the water, let it remain undisturbed for 5 minutes, then rinse the chemical away thoroughly and put them back in the fish tank.

In its weakened state, the algae turn red or becomes clear, and the inhabitants in the aquarium may feed on it.

Hair Algae

They look like hair when they are taken out of the tank. Algae such as hair algae, string algae, thread algae and staghorn algae  grow very rapidly and can be problematic to get rid of. Excess nutrients, (iron included) excess light, or not inadequate nutrients generally cause these algae to thrive.

Decrease the light and iron to disrupt the growth of hair algae. For a clean-up crew, add Amano shrimp, Siamese algae eaters and Florida flagfish. Or uproot them manually using a small brush.

Green Spot Algae (GSA)

GSA is very difficult to clean off. These algae look like hard green spots dotting the tank walls and are slow-growing plants. An imbalance of phosphates or too much light are just some of the many things that can cause them.

To remove the algae from aquarium walls, use an acrylic-safe scraper blade.

Nerite snails like eating GSA and are good to start with to control this type of algae. Unfortunately, their white eggs will dot the entire aquarium. The eggs resemble little sesame seeds and may ruin the aesthetic appeal of the aquarium for some people.

Blue-Green Algae(BGA)

Early on, there will be a strange earthy, musty, swampy, and terrible odor coming from your fish tank. That should alert you of a blue-green algae outbreak. BGA is not an alga but cyanobacteria- meaning a kind of resilient, versatile bacteria that uses photosynthesis like plants.

It may start as a little spot of green algae and progressively grow into a thick slime stretched over your plants, gravel, and decorations. Animals don’t eat this gunk.

Other than the vivid blue-green color BGA can have shades of brown, black, or even red. To get rid of BGA naturally, you will need to remove much of the slime.

Do more water changes to remove excessive nutrients. Clean the filter frequently and reduce the food into the tank. Use a stronger water filter to improve the flow, and add a powerhead. You can also move equipment and decorations around in the aquarium.

Cyanobacteria can be treated with antibiotics. Erythromycin (Maracyn) is safe and does not harm Plant and aquatic life, or the good bacteria in the tank.

To treat BGA, scrub off as much of the blue-green algae as possible and use a siphon to remove it. Vacuum the substrate well and refill the tank.

Catching and treating the outbreak early makes it easier to eradicate. In severe and widespread cases, several repeat treatments may be necessary to eradicate the colony.

Green Water

This is caused by a surge of a single-celled phytoplankton. It makes the aquarium water look like pea soup. The phytoplankton replicates at such a high rate that you cannot mitigate them.

Look out for direct sunlight or excessive nutrients getting into the tank, overfeeding, or too much ammonia; all these in different combinations can trigger green water.

To treat green water, blackout the tank for a few days to deny the phytoplankton

light, which is essential for their proliferation, but your plants are also likely to suffer. Also,

consider purchasing a UV sterilizer to kill algae in a matter of days.

Investing in a water testing kit is a good idea since you can be able to monitor most of the parameters regarding water quality and nutrients. Algae eaters will not completely clean the aquarium, they only eat what they want and when they want.