Algae is a familiar issue for aquarium fish keepers. Excess algae is bad for the aquarium but normal algae is not bad for the aquarium. Normal algae also produce oxygen for the aquarium and acts as a natural food for shrimps and snails.
Since excess algae is harmful to the aquarium, they need to be controlled. I am an expert on how to control algae in fish tanks. I have been keeping fish in aquariums for many years, so I know very well how to control algae in fish tanks.
What is Algae?
Algae in a fish tank is actually a type of single-celled plant or algae that grows in water. It grows rapidly when the water gets extra nutrients and light. Too much algae in a fish tank spoils the beauty of the water and form a dark layer on the tank walls, rocks, or other objects. Some types of algae can be useful as food for fish, but excess algae can make the water in the fish tank dirty and reduce the oxygen balance.
Types of Algae
Generally, 4 types of algae are formed in aquariums, namely: green algae, blue-green algae, brown algae, and red or beard algae.
Green Algae
Green algae is the most common type of algae in fish tanks, it is predominantly green in color and looks like hair or a thin layer. It usually grows on the glass, plants, rocks, and other decorations of the tank. If it is kept in proper control, it helps maintain a natural and healthy environment in the tank. However, excessive green algae can make the tank water look dirty and smoky.
Blue-green algae
Blue-green algae, also known as cyanobacteria, are a type of bacteria that look like algae. Blue-green algae form a thin, slimy layer on the surface of the tank water and are usually green, blue, or dark green in color.
Brown Algae
Brown algae is a type of algae that looks like dust or powder and spreads quickly. They are initially seen in newly set-up tanks and naturally decline within a few weeks. It forms a brown layer on the glass, rocks, and decorations of the tank. Also known as “diatoms” because of the silica they contain.
Red or Beard Algae
Red or beard algae is a type of algae that forms dark green to black layers or small beard-like clumps in the tank. It usually grows in areas with low water movement, such as on rocks, wood, or other tank decorations. It can spread quickly. This algae looks quite rough and feels hard to the touch.
Causes of Algae in Aquarium
The main causes of algae growth in aquariums are excess light, nutritional imbalance, insufficient water changes, etc. Along with the main ones, here are some other common causes that can be responsible for algae growth in aquariums:
Extra Light
Algae, like other aquatic plants, make their own food through photosynthesis, and for this, they need sunlight or artificial light. If the tank has more than 8-10 hours of light, the rate of photosynthesis of algae increases, causing algae to grow rapidly. As a result, algae spread quickly over the glass, rocks, plants, and other decorations of the tank.
Extra light increases the growth rate of algae, which causes them to quickly gain and dominate the aquarium by competing with other aquatic plants, accumulating more nutrients, spreading quickly, and taking up space.
High levels of nitrates and phosphates
Nitrates (NO₃⁻) and phosphates (PO₄³⁻) are very important nutrients for algae growth because they require nitrogen and phosphorus for algal cell formation and reproduction.
When nitrates and phosphates are present in high levels, algal cell division occurs very rapidly and spreads rapidly throughout the tank. Fish waste, excess food, and decaying matter in the tank are sources of nitrates and phosphates.
Not changing the water regularly
The reasons for algae growth, if the water is not changed regularly, are the excess nutrients accumulated in the tank, fish waste in the tank, excess food parts, and decaying organic matter that break down and turn into nitrates and phosphates. Nitrates and phosphates act as nutrients for algae, which helps algae grow rapidly.
If waste and other contaminants accumulate in the tank, the water quality deteriorates. Algae get the necessary nutrients from these contaminants and spread rapidly in the tank
If the water is not changed regularly, the oxygen level in the water decreases and the CO₂ level increases, which helps algae growth, because many types of algae can grow even with low oxygen and can obtain the necessary nutrients from CO₂
Excess food and fish waste
Excess food and fish waste decompose in the water and this decomposition process produces many types of organic matter that serve as a source of nutrients for algae. Due to which the algae grows rapidly.
Excess food and fish waste are helpful in the growth of algae because they add nutrients like nitrates and phosphates to the aquarium water, which act as essential food for algae.
The decomposition process of excess food and fish waste requires oxygen, which creates an oxygen deficiency in the water. Many types of algae grow rapidly in low-oxygen environments and can spread more quickly in these conditions.
Oxygen depletion
Some types of algae can grow easily in low oxygen, while other aquatic plants require more oxygen. When the oxygen level in the water is low and the CO₂ level is high, algae can easily survive in these conditions and grow quickly.
Carbon dioxide increase
Algae, like other aquatic plants, use CO₂ for photosynthesis. If the CO₂ level in the tank is high, the algae are able to absorb this extra CO₂ and photosynthesize faster. This increases the rate of cell division and growth of the algae.
How to Control Algae in Fish Tank
Change the Water
Water changes are an effective method to control algae in an aquarium. Algae usually grow due to excess food, fish waste, and nutrients, so you should regularly change 10-15% of the water every week. Water changes will remove excess food, fish waste, and nutrients from the water, thus controlling algae growth.
Reduce the light
Algae, like other aquatic plants, make their own food through photosynthesis using sunlight or artificial light. If the tank has more than 8-10 hours of light, the algae’s photosynthesis rate increases, causing algae to grow rapidly. If your aquarium gets 8-10 hours of light, reduce the light.
Keep your aquarium in a place in the house where direct sunlight does not fall. Direct sunlight makes it difficult to control the light properly. Do not keep your aquarium near a window or door.
Do not overfeed your fish
Overfeeding your fish causes excess waste and leftover food to accumulate at the bottom of the aquarium, which then decomposes and increases carbon dioxide, which is food for algae. The increase in carbon dioxide increases the algae’s food supply, which causes them to grow very quickly.
Feed your fish at specific times each day and keep the amount to a minimum. Generally, fish should be fed 2-3% of their body weight. When feeding, feed them as much as they can eat in 5 minutes. Leftover food can rot in the aquatic environment and cause algae to grow.
Add fish, shrimp, and snails that eat snails to your tank
You can keep fish, shrimp, and snails that eat snails (Otocinclus, Plecostomus, Glyptothorax, Molly, Scalare) and snails in your aquarium. They eat snails as their food and help reduce the number of snails in your aquarium. This method of controlling snails is called the natural method.
Increase Oxygen in the Aquarium
Aquatic plants naturally produce oxygen, so adding suitable aquatic plants (Java Moss, Amazon Sword, Java Fern, Hornwort, Water Wisteria, Dwarf Lilies, and Crypt Wendtii) to the aquarium will help increase oxygen levels.
To increase oxygen in the aquarium, you can use an air pump and air stone to enrich the water with oxygen. The air stone diffuses air into nanobubbles through the water, which helps increase oxygen levels.
Reduce Carbon Dioxide in the Aquarium
Use a good filter system to reduce carbon dioxide, which helps reduce CO₂ concentrations and keeps the water clean.
Fish and other aquatic animals produce CO₂. So control the number of fish in the aquarium to keep CO₂ levels low.
Clean Algae From Tank Glass
Regularly, you should clean the algae from the glass of your aquarium. When cleaning the glass, use a damp clean cloth or glass cleaning brushes available on the market.
Regularly clean the gravel
Algae often accumulate in the gravel in the aquarium, which needs to be cleaned. If not cleaned, their spread will increase. You can use a gravel vacuum to clean the gravel. Again, you can clean it without a vacuum.
Is Algae Harmful to Aquariums?
The presence of algae in an aquarium is not a bad thing, it is a normal condition. Algae acts as food for aquarium snails. Shrimps, and also increase the oxygen in the aquarium. Create a balanced and healthy environment for the aquarium.
Algae becomes a problem when it starts to grow out of control. If not checked regularly, it can cover the tank glass and degrade the water quality. As a result of the deterioration of water quality, the water changes color and causes problems for the tank inhabitants.
