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8 Great Ways to Help Remove Hair Algae in Aquariums

    planted aquarium

    For some, hair algae is one of the worst nightmares someone can go through in this hobby. It can very quickly take over a fish tank if not kept in check. Once it is around, it can be fairly challenging to remove. Luckily, there are different ways to help eradicate this plant. The tips and tricks in this article should work for both fresh and saltwater aquariums.

    One of the most biggest reasons hair algae takes over, is not ideal water parameters. It will also keep coming back very quickly if water parameters are not maintained at the proper levels. There is no set in stone way on “How to get rid of hair algae”. You will more than likely use each of the following tips. If you want to learn about common reasons algae takes over an aquarium, check out this guide!

    Water Testing & Water Changes

    Whether you are working with a reef tank, freshwater aquarium, cichlid tank or other aquariums, the first thing you should do is check your water parameters. I would really test to see what your nitrate and phosphate levels are. Algae feeds off of these nutrients. Removing hair algae from a reef tank or freshwater aquarium will be much easier once our nitrates and phosphates read zero! One of the main reasons these parameters spike is overfeeding. Consider cutting down on how much you feed your fish and begin conducting more frequent water changes.

    I normally recommend smaller water changes and almost never do more than 25% at a time. Larger water changes could be dangerous for aquariums with high nitrate and phosphate levels. The sudden change in water quality may be bad for your fish, so I normally recommend smaller but more frequent water changes until your parameters reach ideal conditions.

    You can test your water using API Freshwater or Reef Master Test Kits. If you pickup the Freshwater Master Test Kit you will also have to purchase the Phosphate Test Kit separately. If you don’t want the Master Test Kits you can snag the Phosphate Test Kit & Nitrate Test Kit by following the links.

    Physically Remove Hair Algae

    While you are conducting your water changes, it might be a good idea to also take out some of your decorations and give them a good scrub. I usually have a system to avoid removing beneficial bacteria from your aquarium.

    • First: Have two buckets and fill them with aquarium water from your water change
    • Second: Place decorations in the first bucket and use a clean toothbrush to scrub off any hair algae
    • Third: Once most or all hair algae is removed, splash your decoration in the 2nd bucket to give it a good rinse
    • Fourth: Reinsert your decoration into your aquarium

    This method is usually easier to conduct in freshwater aquariums because decorations are more easily moved around. Live rock in saltwater aquariums normally doesn’t get moved around. For Live Rock, I will normally turn off my circulation pumps for a few minutes and physically pluck whatever hair algae I can. Do your best to grab every piece of algae floating around before turning on your circulation pumps! Dispose of whatever algae you remove.

    Add More Cleanup Crew into Your Aquarium

    Once your water parameters are in check, it’s time to introduce and/or add more cleanup crew into your aquarium. You want to wait to add these because cleanup crew such as snails and hermit crabs are far more sensitive to higher nitrates and phosphates compared to fish. I personally would not add fish either until the water is ideal. There are many different animals you can add into both fresh and saltwater aquariums to fight hair algae. For freshwater aquariums consider adding:

    • Snails (nerite, mystery, ramshorn)
    • Shrimp (amano, Neocaridina)
    • Plecos (bristlenose, clown)
    • Otocinclus (great for nano aquariums)
    • Live-bearers (guppies, mollies, swordtails)

    Make sure that whatever you add is compatible with your other fish and water parameters. You wouldn’t want to add shrimp into a cichlid tank because they will quickly become food! Also, certain invertebrates (mostly snails) have a possibility of breeding and taking over the aquarium. Mystery & Ramshorn snail breeding is very common in the aquarium. Nerite snails can breed but their offspring will not be viable in freshwater. You can check out this guide to see some fantastic freshwater algae eaters.

    Saltwater aquariums can have a large assortment of invertebrates and fish that will help remove algae. The following animals might help remove hair algae from your saltwater aquarium:

    • Blennies
    • Tangs
    • Rabbitfish/Foxface
    • Snails (Trochus, Turbo Snails)
    • Crabs (Emerald, hermit)

    There are definitely more algae eating fish & animals available in the hobby. I am listing some of the most common. Make sure the animals you choose to help clean algae are compatible with one another and compatible with the aquarium size! If you want to see some really great algae eaters for a reef aquarium check out this guide.

    Turn Down the Lights

    We love looking at our aquariums, and we may or may not leave our lights on for a little too long. Algae thrives on longer light periods. Consider cutting down you photoperiod to combat hair algae. Your fish tank should go through a day and night cycle. This gives your aquarium time to “rest”. Overall, your aquarium’s health should benefit from a more natural photoperiod. If you cannot keep with a set on/off cycle consider getting a timer for your fish tank. This removes the hassle and gives a consistent day/night cycle for your fish tank.

    Cut Down on Feeding

    Overfeeding will cause nitrate and phosphate levels to spike. Sometimes to very high levels. Cutting down on feeding will help stop water parameters from worsening. If you combine minimizing feeding and increasing water changes, you should be able to slowly bring down nitrate and phosphate levels! You can continue to feed your fish daily, just lower the amount of food that’s added into the fish tank. Once things are under control, you can test increasing feeding regimes. Also, closely monitor how much food you give your fish. Guarantee that what you put in is eaten. Otherwise, remove any extra food!

    Replenish Your Carbon & GFO

    Another way on how to get rid of green hair algae is to update your carbon and GFO. Standard carbon usually lasts a month and should be replaced afterwards. I know sometimes we can forget to swap it but it is definitely a great way to lower nitrate and phosphate levels. GFO (Granular Ferric Oxide) is more commonly used in saltwater aquariums but it can be used in freshwater aquariums as well if you have a reactor. GFO helps remove phosphates in the aquarium, which is important because we want to cut off the algae’s nutrient supply. You can also use Phosguard by Seachem instead of GFO to help remove phosphates in your aquarium.

    Add Plants into the Aquarium

    You can add plants into freshwater aquariums and macroalgae into saltwater aquariums to help keep the aquarium from getting overrun by nuisance algae once again. Macroalgae & freshwater plants will compete with hair algae for nutrients which will overall drive down nutrient levels in the aquarium. This may not work if you do not want plants in your fish tank or have animals that will eat your plants. Macroalgae is also normally kept in a refugium, so it’s not always possible to grow macroalgae due to space limitations.

    Treat your Aquarium with Chemicals

    This is usually my last resort. I do my best to avoid using chemicals in my aquariums. Usually chemicals are a Band-Aid to a much deeper problem. It is better to identify why the algae is growing and remove the source of the problem instead of using chemicals as a quick fix. A chemical called Algaefix can help with removing algae from an aquarium but I have read very polar opinions on it. Many hobbyists have stated that it has caused their fish to act weird and others believe it also killed their fish. This could be because Algaefix depletes the amount of oxygen in the fish tank but I cannot say for sure. Use chemicals with caution and really monitor your aquarium’s behavior if you use it.

    Final Notes

    There is no ideal way on how to deal with hair algae. Every aquarium is unique and will require finessing to get it right. Using a combination of these suggestions should really help combat hair algae and prevent it from coming back. Remember, in this hobby patience is key, so take your time and remove the hair algae correctly instead of trying to find the easy way out!