Bonus: Learn how to keep algae out of a fish tank by downloading our aquarium maintenance tool guide. Click here and get the guide: 9 Essential Tools For Cleaning Your Aquarium.

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Tetra Algae Control
Seachem Flourish
Mag-Float Glass Cleaner
Fluval Pressurized CO2 Kit
Marineland LED Light with Timer
Nualgi Aquarium Nutrition

Links To Amazon

Video: How To Prevent Algae In Your Aquarium

But before we go over each step, here are a few videos you can watch now, that explain some basics about algae growth and prevention.

This video from Fluval has some great tips to prevent algae growth in your aquarium.

So What Causes Algae In Fish Tanks?

If you have an algae problem or you’re just trying to prevent growth, you should understand what causes algae to grow and flourish.

  • Photoperiod too long (Too much light)
  • A recent change in lighting source, fluorescent, LED or Other.
  • Not enough water changes. Don’t be lazy.
  • Too much NPK, Nitrates, Phosphates, Potassium.
  • Un-balanced aquarium. Light, CO2, Nutrients

Algae is a concern for all freshwater aquarium owners, so how do you control it? To learn the best ways for controlling algae in your freshwater aquarium, we have summarized some of the main points from the video and added some of our own.

To ensure algae is kept to a minimum in your tank here are 6 tips on how to stop algae in fish tanks and a few preventative maintenance tricks you should work into your routine.

How To Kill Algae In Fish Tank

1. Control Your Lighting:

  • Control your lighting hours (Photoperiod) If you don’t have live plants 4-6 hours of light per day should be enough. If you do have plant 6-10 depending on the type of plants and lighting you use.
  • Ensure you change your fluorescent bulbs every year.
  • Tank location, don’t expose to excessive sunlight

Note: A good way to ensure you control your light hours is to use a timer. Like this one from Marineland it’s an LED light with a timer. With a timer you can control the length of your “Photo Period” or how long your lights are on

2. Proper Tank Maintenance:

  • Complete weekly water changes 10% every week. Check out our article on how to do a water change the easy way.
  • Test your water & understand what’s in your water.
  • Weekly glass cleaning with a magnetic cleaner.
  • Filter media, rinse out mechanical media.
  • Check filter operation, ensure output and water flow is normal.
  • Reduce phosphate levels with regular water changes or use filter media like Seachem Prime

3. Feeding:

  • Do not overfeed. Feed only an amount that can be consumed in a few minutes. Excess food will break down and provide nutrients for the algae.

4. Keep Live Plants:

  • The best way to prevent algae growth in your tank is to have lots of fast growing plants.
  • Plants help remove algae macronutrients like nitrate from your tank. You could also use Seachem Prime if you need immediate help.
  • Start off with cheap plants and stock your aquarium full, the more plants the more excess nutrients are being consumed by the plants. Once established you can remove the cheap plants and use some great looking plants like….
  • If your plant growth is thick try thinning it out a bit. Algae grow better in thick plants
  • Provide easy nutrients for your live plants to consume. Try using Fluval supplements or other brands.

If you are new to keeping live plants here are 6 of the easiest to care for, fast-growing and best aquarium plants to prevent algae you can start with.

1. Water Wisteria (Hygrophila difformis)

Planterest – Water Wisteria Hygrophila Difformis Bunch Live Aquarium Plant Decorations BUY2GET1FREE

Get Some Water Wisteria

2. Hornwort (Ceratophyllum demersum)

1 Hornwort Bunch - 5+ Stems | Ceratophyllum Demersum - Beginner Tropical Live Aquarium Plant

Get Some Hornwort

3. Red Ludwigia

Aquatic Arts Dark Red Ludwigia - 2 Bunches - Large Live Aquarium Plant

Get Some Red Ludwigia

4. Moneywort (Bacopa monnieri)

Aquatic Arts Moneywort - 2 Bunches - Live Aquarium Plants

Get Some Moneywort

5. Water Sprite (Ceratopteris thalictroides)

3 Water Sprite (Ceratopteris Thalictroides) Live Aquarium Stem Plant by G&Z

Get Some Water Sprite

6. Green Cabomba 

Aquatic Arts Green Cabomba - 2 Bunches – Live Aquarium Plant

Get Some Green Cabomba

Algae control in aquariums

Note: You can super charge the plant growth in your tank using a fluval co2 kit. The unit hangs on back of your aquarium and also has an algae diffuser.

5. Keep some Algae Eating Fish:

Some Fish species can be used to control algae. Below we have listed 6 of the best algae eating fish breeds.

  • Pleco
  • Suckermouth catfish.
  • Most livebearers, mollies, swordtail, platies, guppies
  • The flying fox is popular
  • Snails

If you’re looking for a few more ideas check out these 13 algae eating fish.

Video: The Clean Up Crew! 

This video from NOAH shares their perspective on how to control algae in the fish tank along with their personal favorites for a cleanup crew.

Here are few more to that will help.

  • Amano Shrimp- and other shrimp will also work.
  • MTS- Malaysian Trumpet Snail
  • Oto Catfish
  • Nerite/ Zebra snail
  • Red Ramshorn snail
  • SAE- Siamese Algae Eater
  • Hillstream Loach(es)

Equipment shown or discussed in this article:

Fluval CO2 Supply

The best way to prevent algae growth in your tank is by having lots of live plants and by providing CO2 directly into your tank it will ensure your plants grow fast and healthy.

Fluval C02 Supply allows you to efficiently dissolve CO2 into your aquarium water to ensure that your plants get the most important nutrient available (CO2) to maximize growing conditions.

Fluval Mini Pressurized 20g-CO2 Kit - 0.7 ounces

Try The Fluval Mini Pressurized CO2 Kit

Led Light with Timer

Providing the right amount of light is critical in the battle against algae. Not enough light and you could starve the live plants that will help fight algae. Too much light and your tank could become an algae producing factory.

With a timer, you can control the length of your “Photo Period” or how long your lights are on. If you don’t have live plants 4-6 hours of light per day should be enough. If you do have live plants 6-10 depending on the type of plants and lighting.

Marineland Aquatic Plant LED Light with Timer, 24- to 36-Inch

Try The Marineland Aquatic Plant LED Light

Magnetic Glass Cleaner

One of the easiest ways to prevent the growth of algae is to clean your glass weekly. A magnetic glass cleaner makes this super easy.

Because they are magnets you can clean the inside of your glass/tank without getting wet. You can leave it in your tank along the back or side for easy storage.

If the magnet comes apart then the piece in the tank floats right up to the surface so you can just grab it.

Gulfstream Tropical AGU030SM Mag-Float Glass Aquarium Cleaner, Small

Try The Gulfstream Tropical Mag-Float Glass Cleaner

Filters & Filter Media

Another easy way to keep algae growth to a minimum is to ensure you are using a good filter that can provide you with all three stages of filtration (mechanical, chemical & biological).

Fluval 407 Perfomance Canister Filter, Black

Get The Fluval 407 Canister Filter

Plant Supplements & Nutrients

If you have a planted tank one of the ways to ensure your plants are getting enough nutrients is by using the CO2 systems noted above. However, a cheaper way to also help your plants stay healthy is to use a plant supplement like Seachem Flourish Excel.

All growing plants need a source of carbon and flourish provides a bioavailable organic carbon.

Seachem Flourish 500ml

Seachem Flourish 500ml

Water Conditioners

Water conditioners are a cheap way to keep the water condition in your aquarium clean. Seachem Prime as an example removes many harmful chemicals that can encourage algae growth.

It’s super easy to use, you just add the recommended amount to your tank during each water change each week. 

Learn more about Seachem Prime Water Conditioner in our detailed review

Seachem Prime 500ml

Seachem Prime 500ml

If you can implement most of the tips above and start to use some of the equipment in your weekly routine you should see a noticeable decline in algae growth.

Conclusion: How to control algae in an aquarium? prevention is key, so don’t get lazy.

Tetra Algae Control
Seachem Flourish
Mag-Float Glass Cleaner
Fluval Pressurized CO2 Kit
Marineland LED Light with Timer
Nualgi Aquarium Nutrition

Links To Amazon