In established aquarium can Algae be beneficial, but harmful if not under control. On the other hand, algae is also a food source for some fish. Aquarium algae spread by spores, which can be transported on live plants, on fish, and even in the gut of newly bought fish. Bad news some algae spores are airborne.
Are algae good or bad for your fish tank? Algae can be beneficial for established aquariums by an extra layer of filtration for nitrates, phosphorus, ammonia and other potentially toxic by-products from your fish and plants. Algae can be a fish food source. High level of Algae is also an indicator of a neglected fish tank.
So it is easy to say algae will visit your fish tank also, it is a matter of time. It is a matter of how good you are prepared to control it and reduce it. It can be definitely called an uninvited guest also, let’s dive deeper into it.
You have worked so hard to set up your freshwater aquarium. You have gotten beautiful fish, gorgeous décor, only the best not cheap substrate and filtration systems, and only the finest algae. Wait. Algae? Who invited algae to your tank party?
The bad news is that algae will always find a way to grow in your aquarium. This invasive plant will quickly take over your entire tank, using valuable nutrients and putting a strain on the bio-balance.
There are many types of algae, and not all of it is bad for your tank. There are also many treatment options for getting rid of algae and returning your tank to its pristine beauty again.
How did I get Algae in my Aquarium?
Algae is spread by spores, which can be transported on live plants, on fish, and even in the gut of new fish. Some algae spores are airborne. Once the spores are in the water, they can lie dormant for a very long time until the conditions are right for them to bloom.
- Once algae have overtaken the tank:
- Aquarium glass will be covered with algae
- Décor will be covered with algae
- Filters and other equipment will work harder, potentially breaking over time thanks to algae
- The bio-load of the tank will be unbalanced
- Plants can be overtaken by algae and potentially die
What is Algae?
Formerly considered a plant, algae is classified as a protist, a group of living organisms that do not fall under the category of fungus, animals or plants. This group also includes the amoeba and paramecium, those science class favorites from school. Protists generally consist of one cell or form colonies of cells. They reproduce asexually by splitting their cells, so it’s easy to see why a small problem in your aquarium can quickly spiral out of control.
Is Algae a plant?
Algae have chlorophyll and use photosynthesis, like plants. Algae, however, lacks leaves, root systems, or true stems, unlike organisms that are classified as plants. Algae can be microscopic, like the Micromonas Pusilla, or very large like the giant kelp reaching nearly ten meters in length found along the coastlines of the Pacific Ocean.
It is not confined to fresh or saltwater environments, though, and can be found on dry land in tropical regions where it is moist and warm as well as in deserts where they have evolved to survive harsher conditions.
Practical Use of Algae out of Fishkeeping hobby
Algae has many practical uses and is farmed in a process known as Algaculture. Algae can be used for medicines, cooking oils, fertilizers, natural food coloring and dyes, and bio-plastic products. Algae is high in Omega 3 and Omega 6 fatty acids and is frequently used for these ingredients in many health supplements. With that being said, please do not try to extract algae from your fish tank to supplement the diet.
Algae as a help
Sugar substitute products can be made from algae, as can cosmetics. Environmentalists use algae to filter water and clean up pollutants from wastewater management sites, filtering CO2 released into the air as part of our carbon footprints, and fuel. Additionally, algae can be a key component in the production of hydrogen.
While none of this applies to the casual aquarium keeping hobby, it is still good to know that algae can be useful rather than just a menace to your fish tank.
Types of Algae
The term algae refer to the organisms as an entire group; this group can be broken down into many distinct types. Of these many types of algae, seven are well-known plagues to aquarium owners everywhere. Each has its own life cycle in your tank and can be caused by a variety of different things.
1 – Brown Algae
Brown Algae is a common complication many freshwater aquarium enthusiasts face when first setting up their fish tanks, but as additional problems arise within the tank brown algae may appear again. Brown algae do not require bright light; it thrives in low lighting, so reducing the amount of light in your tank will not help to eradicate brown algae.
Brown algae will appear as fluffy spots on your plants, glass, substrate, rocks, and other décor.
Brown algae is caused by
- Low lighting over the tank or the expiration of your light tube’s usefulness
- Overfeeding, causing high levels of phosphates in your fish tank
- Clogged or improperly working tank filters
- High levels of nitrates in the tank
Brown algae live best in water situations that may be harmful to your fish, so its appearance could mean you have other unhealthy things going on in the tank as well.
How to fight brown algae?
- Regular water changes
- Replace light bars and increase the duration of the lighting cycle
- Increase the intensity of your lights over the fish tank
- Change and clean out your tank filtration system
- Reduce the nitrates in water to 20ppm or less
2 – Blue Green Algae:
This species is more of a bacteria than algae, and it can have devastating effects on your overall aquarium health. It is distinguishable by its foul odor and very slimy feel. Blue Green Algae will coat your gravel, décor, the border of your gravel against the glass, and usually the back surfaces of the aquarium in large sheets.
As quickly as you can manually get rid of blue green algae, it will reappear and spread rapidly. Blue Green Algae is, in fact, one of the oldest living organisms on the planet. While it is not inherently dangerous to your aquarium inhabitants, it is very unsightly and fast spreading.
Blue Green algae is caused by
The biggest cause of Blue Green Algae is poor water circulation. So you definitely need to pay attention to:
- Dirty fish tank filters
- Dirty gravel and substrate caused by dirty fish tank filters
- Generalized poor circulation of water in the tank
- Additionally, if your fish tank has high nutrient levels or a very low level of nitrates, blue green algae can appear
How to fight Blue Green algae?
This is a very tenacious species of algae, but you can combat it by improving the circulation in your tank. You could try:
- Considering air stones to move water constantly
- Cleaning out filters and making sure the outlet valves are working properly
- Stirring up the top layer of your substrate so the algae can be filtered out
- Vacuuming the algae out of the tank
- Potential help can be also getting some Malaysian trumpet snails, they love to love to aerate through the sand and gravel for more info see the post about Freshwater Aquarium Snails
In addition to improving water circulation, test the parameters in your tank to be sure your tank water is balanced properly. Unfortunately, no matter how hard you try, some small pockets of blue green algae may still survive in small, hard to find areas and bloom again.
3 – Green Hair Algae
By far, Green Hair is the most common algae you will come across in your freshwater aquarium. This algae can have many different appearances such as hair or spots and can be found independently or together in groups. It can grow to an impressive length of 1 inch and quickly overrun your fish tank.
Green Hair algae is caused by
Some common causes of green hair algae include:
- Low nitrate levels
- Too much light exposure, either in duration or intensity
- Low CO2 levels
How to fight Green Hair algae?
Green hair algae are relatively easy to eliminate, however, and you can try:
- Adjusting the amount of exposure to light for your tank
- Increasing water nitrate and CO2 levels
- Manually scraping or vacuuming the algae off a surface such as a tank glass and decórs
4 – Green Spot Algae:
This algae, also known as disc algae, can be found on your plants and aquarium glass walls. It typically presents as small, rounded green spots. These algae spots are hard, rather than soft compare to green hair algae, and will stubbornly adhere to surfaces. Eventually, the spots will spread to a continuous hard sheet on affected areas.
Green Spot algae is caused by
- Low levels of phosphates and CO2
- Too much light exposure
This is a very difficult algae to physically remove and will need to be scraped off surfaces, usually with a razor or a commercial tool made specifically for that purpose.
How to fight Green Spot algae?
Other ways to rid yourself of green spot algae are:
- Check the parameters of your water to be sure they are balanced
- Avoid overfeeding the fish
- Magnet scraper for fish tank glass
- Reduce the amount and intensity of light in the fish tank
5 – Black Red Brush Algae:
This species tends to grow along the edges of plants and décor in your tank, as well as near the filter system. As its name implies, the algae will grow in short bushy tufts of black or red. It is also known as black beard algae, due to its beard-like appearance on the edge of your plants. Black red brush algae clings stubbornly to surfaces, making it very difficult to remove.
Black Red Bush algae is caused by
This algae usually indicates an imbalance in the parameters of your water, such as:
- High water hardness in a tank
- Constant changes in CO2 levels
- Low CO2 levels in a tank
How to fight Black Red algae?
If left untreated, this stubborn species will quickly overtake and kill your plants. Because black red brush algae is linked to improper water parameters in the tank, it can be combatted by:
- Improving and stabilizing CO2 levels in tank water
- Additionally, improve water circulation in your aquarium
- Increase lighting exposure for tank
6 – Stag Horn Algae:
This species can grow on plants and rocks, with various colors from gray, to green, black, and even red. Stag Horn Algae grow with offshoots that resemble a deer’s antlers, or branches on a tree. Most algae eaters will not eat this species, and it is hard to manually remove once established.
Stag Horn Algae is caused by
Stag horn algae are almost always directly related to dirty and neglected fish tanks. These species thrive when:
- Fish are overfed and the mulm (fish wastes and food debris) is not cleaned from fish tank properly
- Fish tank filters are dirty
- Gravel is not cleaned or vacuumed
- Low CO2 levels
- Plant fertilizers that are high in iron being used
How to fight Stag Horn Algae?
Since stag horn algae are usually associated with dirty fish tanks, steps can be taken to clean your tank and rid yourself of this pesky algae species:
- Do not overfeed your fish
- Vacuum gravel and substrate your tank regularly
- Check that the filter is working properly, and clean it if needed
- Increase your CO2 water level
- Water changes in tank
7 – Green Water
This is probably one of the most aggravating algae species for freshwater aquariums. The entire tank will turn green and cloudy with the presence of tiny, single-celled, free-floating, algae called planktonic algae.
Green water is usually caused by
- Too much light, both in the tank or where the tank has been placed
- Overfeeding the fish
- Gravel or substrate getting moved, releasing trapped dirt
- High ammonia or nutrient levels in fish tank water
How to get rid of Green water in the tank?
It is easy to panic when your beautiful aquarium has turned murky and green, but you can usually reverse it by:
- Not overfeeding the fish
- Keeping gravel vacuumed and clean
- Checking water parameters and correcting them
- Moving the tank out of any direct light sources, such as sun
Is Algae bad for Aquariums?
Believe it or not, small amounts of certain types of algae are beneficial for your aquarium. Plants and trees benefit land creatures by filtering toxins and producing oxygen; this is exactly what algae do for your tank. Of special importance is the algae’s ability to cycle nitrogen components, like ammonia and nitrates. This is especially significant if your aquarium does not feature live plants that cycle the nutrients naturally.
What fish does eat algae?
Some species of freshwater aquarium snails and dwellers love to nibble on algae in the fish tank. Some livebearers, such as Mollies and Swordfish, Butterfly Splitfins, The Siamese Flying Fish, and many cichlids will enjoy an algae snack.
Adding algae eaters, catfish, snails, and shrimp will make your tank more diverse while keeping the algae population under control. Read more about Algae Eaters for Fish Tank.
Some types of algae are a good sign that your aquarium is healthy.
What kind of Algae is beneficial for the fish tank?
Brown algae and green hair algae are the most common types of algae in most tanks, and these are very beneficial for additional filtration of nitrites and harmful toxins.
What kind of Algae is harmful to the fish tank?
If other algae are present, like staghorn algae, it could be an indicator that something is not right with your fish tank. Correcting the parameters to rid yourself of harmful algae species will also allow you to fix issues that will potentially be dangerous for your fish if allowed to continue unchecked.
I like the look of a controlled amount of algae in the fish tank, it looks more natural.
Some aquarium enthusiasts like the look of a controlled amount of algae in their tanks, thinking that it looks more natural. These tank owners will keep their algae confined to certain areas or rocks and allow it to blanket the back glass of the aquarium. Too much algae growth, conversely, will make the tank look neglected and dirty. Algae can be kept in smaller, controlled amounts to add to the beauty of the tank.
Algae is the only source of Vitamin A for your fish. Thanks to Vitamin A, fish colours are bright and have beautiful shine.
Fish are unable to produce carotene, an important vitamin that aids in the production of Vitamin A. Fish will get carotene from the plants and algae in the aquarium. One benefit of Vitamin A for fish is that it is what allows them to have such brilliant, beautiful colors.
Algae is not in and of itself harmful to your fish, but the underlying problems that allow the algae to form could indicate issues in the tank that are potentially very harmful to them.
However, it also does add to the bio-load of your tank. Algae uses nutrients just like aquarium plants do, and too many algae can cause imbalances. Additionally, most fish and algae eaters will not touch some types of algae, like staghorn algae or brown algae. These algae must be controlled in other ways, or they will quickly overgrow the tank and smother your plants.
How to Control Algae Growth Naturally
The best way to control algae growth is naturally or by changing some of the tank parameters themselves. Feeding, manual removal, temperature adjustments, exposure to light, and checking the nutrient levels of your tank are easy, natural methods to control or eliminate algae.
7 easy ways how to naturally keep algae grown under control
1 – Control the amount of light for the aquarium:
Depending on the species of algae you are combatting, you may need to keep your aquarium lights on longer or shorter cycles. Additionally, using a UV light or a UV sterilizer will control the algae as well. Algae will proliferate in sunlight, so setting the tank up in full sunlight is not a good idea. A complete blackout may be necessary if the algae have gotten very bad; the lights should be left off for several days while the filter is set for maximum water circulation. This will prevent photosynthesis and encourage the algae to die off, but be aware it could adversely affect your live plants as well.
2 – Manual removal of algae directly from the tank
You can buy several types of manual algae removal tools in any aquarium supply store. These include sponges, scrapers, mitts, and magnets to remove algae from the sides of the tank. Live plants and décor can be removed and cleaned with a weak solution of bleach, thoroughly rinsed and allowed to dry before being placed back into the tanks. Investing in an aquarium vacuum will help clean the gravel and décor as well.
3 – Increase the number of live plants in a tank
Increasing your living plants in moderation will help to slow algae growth. The plants will compete for the same nutrients that the algae need to survive, and certain plants are known to be natural algae repellents.
4 – Monitor your water quality in the fish tank
Make sure your levels are all in good alignment and then try to avoid the things that will cause imbalances such as overfeeding, not cleaning the filters, overcrowding, and leaving debris at the bottom of the tank. Maintain the balance of the tank with regular water changes, as well.
5 – Improve water circulation in the tank
Invest in a high-quality filter with good outlets, make sure the filters are all clean and running smoothly, and consider air stones to keep water moving in your tanks. If you guess that algae will not settle in areas that are subject to movement, you are totally right.
6 – Get fish that will help you control algae – “algae eater”
Some fish species will snack on algae, while others will eat it exclusively. Snails and shrimps will eat algae, as will catfish, Plecostomus, Chinese Algae Eaters. Several ornamental fish will eat algae as well, such as Mollies. Most algae eaters are peaceful, but some do require more than one to thrive. Always make sure your fish are not aggressive; some fish enjoy a tasty feast of shrimp or snails. Be aware when choosing algae eaters that not all of them will eat every type of algae, and that these fish will need to be supplemented with vegetables or special algae discs and other types of specialized foods.
7 – Try Bacteria
One organic method involves solutions that contain bacteria. These bacteria will eat the algae itself, but will also eat and absorb excess nutrients that the algae need to survive.
Chemical Removal of Algae
Chemical water treatment to remove algae is always a last resort. The chemicals and treatments that kill the algae can also harm your live plants as well. Additionally, killed algae with chemicals will affect your bio-load negatively. Remember, dead algae is debris in your water, the same as food and dead plants or leaves.
If you have tried to remove algae naturally, however, and are unhappy with the results, there are a few options.
3 recommended solutions on how to get rid of algae with chemical removals
1 – Hydrogen Peroxide
Use only a 3% solution, and use it with a Sochting Oxydator to doses from 8 to 35 milliliters per fifty liters of water. Try to avoid pouring it directly onto fish, and plants. You will cause an issue of discolored or even death. Or even try cheap Sochting Oxydator Mini from Amazon.
2 – Antibiotics
While antibiotics are useful against some algae, they will kill beneficial bacteria in your tank as well. Before use pls, read instructions.
3 – Proprietary Chemicals
These are the solutions you find in every aquarium supply shop, and while they can be successful in killing the algae, they may be quite harmful to plants and fish. Additionally, the tank may suffer from the overload of the dead and dying algae. Before use pls, read instructions.
Algae: The Good, the Bad and the Hairy
Algae can be beneficial for established aquariums by adding an additional layer of filtration for nitrates, phosphorus, ammonia and other potentially toxic by-products from your fish and plants. It can be a food source for some fish or an indicator that all is not entirely well in the aquarium.
Keeping controlled amounts of green hair algae can be helpful, but other types are invasive and without any real benefits. It is possible to have too many algae, however, because algae compete with fish and plants for the same nutrients and can cause a bio overload in the tank.
If you want to control algae, the natural methods are always the best first choice because chemicals and antibiotics can potentially harm your fish and plants, and unbalance the bio-load when they die in large quantities.
While it seems the focus in fishkeeping is always on the clean fish tank, any true aquarium enthusiast will tell you that, in small controlled amounts, some types of algae are both attractive and beneficial for your tank. Happy fishkeeping.