How to Clean Algae From Fish Tank

Algae forming in your fish tank is never a nice experience.

Of course, some algae in a tank can be a good idea, but as soon as it begins to take over, it starts to use too much oxygen.

This can lead to the fish not getting enough oxygen and dying overnight.

To avoid this, we need to know how to properly clean our tanks to avoid algae buildup.

If you are interested in finding out how to rid your tank of unwanted algae, or want to know why algae forms, keep reading!

We will be diving into everything algae today. Let’s get to it.

Contents show

What Causes Algae to Form in Your Fish Tank?

Algae forms because of an overflow of nutrients and light in the water of the tank.

When the conditions are perfect, it will bloom, potentially turning your tank green overnight.

Algae can be a good thing, as long as it stays under control.

Many people like to have algae-eating fish or water-dwelling creatures in their tanks to help them control the algae, but this doesn’t always work.

Depending on your tank hygiene habits, having an algae eater or two probably won’t make much of a difference.

Too much nutrition and light in the water aren’t the only things to help algae grow.

Over feeding our fish is one of the most common reasons for lots of algae in the water.

Additionally, waiting too long between water changes can lead to high levels of algae in your tank.

The light that makes the water a perfect place for the algae can be from the aquarium lights or direct sunlight, and overfeeding your fish can lead to nutrients seeping into the water.

There is usually more than one contributing factor at play when algae begin to take over your fish tank, and figuring out the reason is very important to the health of your fish.

How to Prevent Algae From Forming in Your Fish Tank?

Before diving into how to clean the algae from your tank, let’s take a look at how to prevent it from taking over in the first place.

There are some key things to consider, so take a look at your tank and see if you are making any of these mistakes.

Limit the amount of light – since algae thrives on light, whether natural or man-made, it’s a good idea to keep track of the light your tank gets. Make sure your aquarium is not in direct sunlight as the sunlight will lead to algae growth. Make sure that any artificial light you are using is not stronger than it needs to be, and ensure that it isn’t on for more than 10 hours a day. To keep track of this, use a timer that will turn the lights on and off every day, so you don’t have to worry about remembering.

Complete frequent water changes – this is probably the most important step in avoiding algae buildup. You need to carry out 10-15% water changes every week. This will help keep the nutrients in your water low enough so that algae cannot take advantage of the free food.

Feed your fish less – there is a good chance that you’re feeding your fish too much. As a general rule, you should only feed your fish as much as they are able to eat in two to five minutes. The uneaten food will otherwise increase the levels of phosphates in the water, which will make it the perfect environment for algae. If you see that there is uneaten fish food stagnating at the bottom of the tank, remove it as soon as you can.

Have some algae-eating fish – having a few algae-eating fish in your tank can help you a lot, but don’t expect them to eat everything if you have let it get too far. Some great algae-eating fish include otocinclus or plecostomus, but they may not eat every kind of algae.

Clean algae as it forms – removing algae as you see it is one of the best ways to stay on top of the problem. If you see new algae growing on the glass or rocks, remove it promptly. Whenever you carry out your water changes, vacuum the gravel too, to get rid of any unwanted algae.

Learn about the water you are using – all water will have different properties, and some water is higher in phosphates than others. If your water is high in phosphates, get phosphate removing chemicals at your local aquarium or pet store, or find a different water source. While you test for phosphates, also check the nitrite levels, as this can also be extremely harmful to your fish.

Have live plants in the tank – you can always depend on live plants to do a lot of work for you. Keeping live plants in your tank will help keep the nutrient levels of the water lower, since the plants will absorb it. If there are fewer nutrients left in the water, there is less food to act as fuel for the algae to get a hold and grow.

Types of Algae

There are various types of algae that can form in your tank, and each of them have to be dealt with differently.

Knowing the type of algae growing in your tank will also help you find out what the cause of its growth.

Blue-Green Algae – this is also known as smear algae or slime, and it usually caused by excess phosphate and nitrates in the water. The most important thing for this is making sure you take care of the water and remove the excess nutrients.

Green Algae – also known as spot algae, this species is a healthy type and is actually good to have, as long as you stay in control of it. This is the type of algae that most algae-eating fish enjoy, so it’s a great food source.

Beard or Red Algae – this type of algae frequently appears on plants and is the most difficult to get rid of. To get rid of it, dip the plant into a 5-10% bleach solution for a couple of minutes to kill the algae.

Brown Algae – this is also known as silica or gravel algae, and is common is new tanks. This type of algae will coat the tank and will typically go away, but it can be wiped off easily. It is harmless, but doesn’t look very nice.

Green Water – green water is also called algae bloom. This happens when microscopic pieces of algae stay in the water. To find out more about algae bloom, check out my post on algae bloom, which covers what it is, and how to deal with it effectively.

Cleaning Algae From a Fish Tank

There are five main methods you can try to clean algae from your fish tank.

Bear in mind, you should try to keep track of why the algae might have formed in the first place to effectively deal with it, but these methods should help you get it under control.

Manually remove the algae with tools – for immediate results, get your hands dirty and get to work cleaning the algae manually. Use an algae scrubber to get algae off the walls of the tank, and use a glass cleaner with scraper blades to get rid of the stubborn stuff. For the algae covering the decorations and rocks in your tank, a simple toothbrush will do the trick. Finally, using a siphon to get the sand and gravel out of the tank is an effective step in removing algae from the tank.

Get rid of the excess organic material from the tank – make sure you remove organic material such as fish waste, uneaten food, and decaying plants (or fish) from the water as soon as possible.

Treat the water with an algae inhibitor – algae inhibitors are a great way to keep your tank looking fresh, but always follow the instructions carefully.

Get algae-eating fish – this isn’t always the best option, as not all fish will eat all algae. Do your research to find out which is best, or it will work at all, and give it a try. This option is really simple and usually effective, but does have its limitations.

Be mindful of how much light your tank is getting – as we know, too much light creates the perfect environment for algae to thrive. Keep the tank away from windows and direct sunlight, and limit the hours that artificial lights are on.

Control the amount of nutrients in the water – like the point above, you need to control the nutrients in the water. Feed your fish as much as they can eat in five minutes, and even skip the feeding for a day of the week. This will force them to eat any food that has fallen to the bottom, reducing the amount of organic waste in the tank.