How To Get Rid of Hair Algae in a Planted Tank?

Hair algae in a planted tank can be extremely frustrating. It can make your beautiful aquascapes look terrible within weeks. This actually happened in one of my newer planted tanks a couple of weeks ago. Luckily it’s one of the easier types of algae to deal with.

Hair algae should be removed manually, which can easily be done with an old toothbrush. To permanently remove it from a planted tank, it’s important to tackle the cause of the algae. Hair algae is often caused by too much light or an imbalance in nutrients or CO2. Fixing the cause is crucial.

To get a better understanding of hair algae, it’s important to read this article to the end. I will make sure you can recognize the cause of the problem in your tank. I tried to make it as helpful as possible.

Where does hair algae in your planted tank come from?

The first element that can become the onset of algae production in your aquarium is the things that you put into it that have been living in or come from other water bodies. These items most likely have algae on them and thus can kickstart the growth of algae. It might come from the plants you add, fish you introduce or from other living components present within the aquarium like rocks and driftwood.

Removing hair algaerequires you to understand the possible culprit that might have a few strands or a tuft of algae growing on it. The plants, shells of snails, decorations or equipment you put in there are likely reasons for such uncontrolled algae growth as they might have some algae on them.

Algae itself is microscopic, and it might enter your aquarium via multiple sources, and the airborne spores are one of such sources. This makes it so annoying, because even if you’re extremely careful with what you put in, algae will still find a way. Therefore, it’s important to prevent excessive growth and know how to handle any signs of hair algae in the first place.

Prevention of hair algae: the first line of defense

Like most things in life, the green algae growing in your aquarium is inevitable. There is only so much you can do about making it stop growing, but there are other precautions you can take to minimize its spread and impact. Usually, the hairs of algae will suck up all the essential nutrients present in the water and leave very little for some of the plants that are slow growing, and the same goes with the sunlight; it tends to absorb it all. If you want to prevent its spread, then the following are some of the methods that you can try.

Introduce algae eating fish or snails

You could add fish like otocinclus or algae eating snails like netrite snails. It might work in some scenarios and in others it might not, but it could be worth a shot. You can easily find some fish and invertebrates with a taste for algae that can help you scrub it out pretty well. For some aquarists, it might not be a great idea to buy a fish just for the sake of getting rid of all that algae. If that algae-eating fish can do you some good and works with the rest of your fish stock then it is worth a shot to go with this idea.

I think it’s super important to doublecheck whether the fish, shrimp or snail that you add to your tank fits with the rest of the aquarium. Make sure they won’t fight or get eaten. If you can take care of them, they could be a welcome addition to your planted aquarium.

Manually remove all hair algae

It’s super important that you try to find the cause of your algae. If you do not fix the cause, removing it will only be a way to treat the symptoms. Luckily for us, removing hair algae is quite simple. All you need is a toothbrush and some patients. The green hair algae does not stick to any of the plants, so it’s easy to rip loose and remove completely.

If you want your hard labor to have an effect as long as possible, you need to scrub all the possible places and corners where algae has been growing. Removing all algae is a great way to make your tank look nice for a while, but remember it’s only temporary: the algae will grow back in a matter of weeks or even days.  

In order to permanently improve the looks of your tank and keep hair algae at bay, you need to find the cause/problem and tackle it!

Different ways to prevent hair algae from growing back

The most plausible reason for an increased growth of hair algae is a CO2 or nutrients imbalance. An imbalance in CO2, nutrients or too much light can cause hair algae to grow rapidly. Most planted tank owners and even professional aquascapers at first think that their hair algae issue is a nitrate or phosphate related problem, but almost always, it is tied with CO2.

If there’s something wrong with the amount of CO2 or nutrients in a tank, plants won’t be able to grow as well which gives hair algae an opportunity. Fixing the problem will allow plants to grow at their optimum speed again, reducing the hair algae opportunity.

Below I’ve written some of the fixes that will help you eradicate the algae issues and potentially make them disappear once and for all;

1. Reduce overall lighting to slow down plant growth

Lighting is essential for the plants that are present within the aquarium to do well and grow to their full potential. However, with too much light at hand, plants want to grow super fast. Often, there’s not enough CO2 nor nutrients present to grow at those speeds. Because of this, not all the energy of the bright lights can be absorbed by the plants, which leaves light for algae which are way more efficient than plants.

What you can do here is decrease the overall lighting that is hitting your aquarium. This way, your plants will be less tempted to grow fast. This will reduce the amount of required CO2 and nutrients, allowing for a decent balance overall. It also gives plants a chance to use light, CO2, and other nutrients in a more productive approach; algae won’t be able to get an opportunity to scoop over and disturb your aquarium’s ecosystem.

About eight hours of light is more than enough for the plants to run their normal everyday growth cycle. But if the algae overgrowth problem is intense and consistent, then you might have to cut the lighting cycle by a few hours. If you can’t manually take control of the schedule, then installing a timer can do the trick for you as it will be able to turn the lights on and off at the same time every day.

2. Stabilizing the dissolved CO2 in your planted tank

If you are not using a CO2 system already within your aquarium and are facing green hair algae, then it could be time to implement one. It will add balance to your aquarium that might have been lacking. It might be a little too pricy, but it is the right step towards making the algae problem slip out of your way permanently. Implementing this system will flush your aquarium with the necessary CO2, and other plants will be able to grow lavishly, thus outcompeting the green algae growth altogether.

In short, with more CO2 you can allow plants to outcompete algae because there’s a balance between light, nutrients and CO2. If you do not want to invest in additional CO2, you’ve got to reduce lighting and nutrients to find balance in your planted tank.

Tip: also read my article on how to add CO2 to a new planted tank the easy way. You can find that article here on my site.

3. Double check the amount of dissolved CO2

Even if you have a CO2 system set up and running, make sure that it is working the way it should. Check the current CO2 levels and if these are not enough, then increase the amount by increasing the overall dosage within the CO2 apparatus. If there’s too much CO2 you will also have an algae problem, but it probably won’t be green hair algae.

If you manage to find the correct CO2 levels in your planted tank, you will see hair algae in the aquarium slowly disappearing over the course of several weeks. This change is permanent, and there is no need to worry about the algae springing up provided the CO2 concentration and dosage are managed and controlled over time.

Another thing to make sure of is that your macro and micronutrients are also present in considerable amounts and balanced to make sure that the problem remains solved for extended periods. For this reason, I always recommend that you use a liquid plant fertilizer. Algae can start growing when there’s an overall imbalance in your tank.

4. Consider adding liquid carbon to reduce hair algae

If injecting pressurized CO2 is not an option, you might want to consider adding liquid carbon. Although the name suggests otherwise, it’s by no means actualy liquid carbon. Instead, it’s a solution that contains (a diluted version) of a chemical that improves the plant’s ability to obtain CO2 from the water.

It might not be the most subtle way to cover the CO2 deficiency for your plants, but it does a pretty good job when it comes to fighting the battle against hair algae. It behaves strongly towards the hair algae and almost chokes it out, which leads to a quick and consistent algae takedown throughout the aquarium. You can use it directly to the most infested area and will be dazzled with the progress it makes. There are many different options available from different brands and stores.

5. Optimize water circulation in your planted tank

If your aquarium comes with an inadequate water circulation system, then it is recommended that you repair or change it to a better or a more elevated one. This way the nutrients and CO2, along with the water, will reach every side and corner of your aquarium.  

Not only this but the algae itself will start decaying much faster as CO2 is making its way to it. You can increase the filter flow if you believe that there are some parts or sections within your aquarium where water is not making its way.

Remember to tackle the root of the problem

It is essential to combat the growth of hair algae in the aquarium, but it can’t be done until you take some preventive measures and get down to a reasonable solution after verifying the problem at hand. But once you are done with the above-mentioned steps, you will be less likely to face this issue in the future and can get a grip on the overall situation.  

My Favorite Fishtank Products to Make Life Easier

Over the years I’ve found a variety of products that make the fish keeping life so much easier. Whenever someone asks me what products I recommend buying, these are the first 5 items that come to mind. I’ll briefly list them below and state why I love them so much. I’m 100% sure you’ll love them!

1. A good gravel vacuum; Without a gravel vacuum, cleaning the substrate of your tanks is near impossible. Whenever I want to remove some of the sunken detritus from the bottom of my tank I’m happy I’ve got one of these. They’re available here on Amazon and I highly recommend them!

2. Liquid plant fertilizer; It’s no secret that I do not like nutritious aqua-soil. It makes a mess and only works a given amount of time. Instead, I always use a liquid aquarium plant fertilizer. Everyone who keeps live plants needs it, it’s not that expensive and makes your plants grow better. This is the one I use and recommend.

3. A set of aquascape tools; I love keeping plants, but planting and reorganizing my aquarium was difficult until I got a set of these tools. It’s much easier to plant any kind of plant compared to using my thick fingers. They’re also available here on Amazon.

4. A liquid-based water test kit; ever since I’m able to accurately test my water parameters, keeping fish became less stressful. Before I was always stressed that my water parameters were wrong, but using a kit such as the API Master kit, which is available here, I can measure this. It really is essential to successful fishkeeping.

Bart Sprenkels

I have been keeping multiple aquariums since I was 18 years old. Just like many of you, I started with two goldfish but quickly learned they were not suitable for aquariums. Later, I switched to a tropical community tank and I also have two pet musk-turtles in a bigger aquarium. You can read more about me here.

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