3 Ways To Keep Aquarium Water Clear - WikiHow

Home » How To Keep Fish Tank Clean » 3 Ways To Keep Aquarium Water Clear - WikiHow

Maybe your like

Skip to ContentQuizzes
  • Home
  • Random
  • Browse Articles
  • Quizzes & Games
  • All QuizzesHot
  • Love Quizzes
  • Personality Quizzes
  • Fun Games
  • Dating Simulator
  • Learn Something New
  • Forums
  • Courses
  • Happiness Hub
  • Explore More
  • Support wikiHow
  • About wikiHow
  • Log in / Sign up
Terms of Use wikiHow is where trusted research and expert knowledge come together. Learn why people trust wikiHow How to Keep Aquarium Water Clear PDF download Download Article Explore this Article methods 1 Setting Up Your Aquarium 2 Maintaining Your Aquarium 3 Troubleshooting Cloudy Water How Do You Keep Aquarium Water Clear? + Show 1 more... - Show less... Other Sections Expert Q&A Tips and Warnings Related Articles References Article Summary Co-authored by Craig Morton

Last Updated: July 4, 2025 Approved

PDF download Download Article X

This article was co-authored by Craig Morton. Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance. wikiHow marks an article as reader-approved once it receives enough positive feedback. This article received 13 testimonials and 96% of readers who voted found it helpful, earning it our reader-approved status. This article has been viewed 262,894 times.

An aquarium with clear water is a sign of a healthy environment. Fish need clean and healthy water in order to thrive and live. Uneaten food, fish waste, and plant debris raise the ammonia, nitrite, and nitrate levels of the tank and make it unsafe. There are a number of ways for you to keep your aquarium water clear.

Steps

Method 1 Method 1 of 3:

Setting Up Your Aquarium

PDF download Download Article
  1. Step 1 Leave the cloudy water. 1 Leave the cloudy water. This is called "New Tank Syndrome", and sometimes will occur when a tank is recently set up. Many times cloudy water will disappear on its own while the water environment adjusts. Often, cloudy water is a result of a mixture of microscopic organisms, such as bacteria, protozoa, and micrometazoa. These organisms come from your fish, food, and waste. Usually, the tank will be balanced out and cleared up within around a week.
    • Be patient. Before adding chemicals or trying to do anything drastic to fix the cloudy water, remember that the aquarium is full of living organisms. Figure out why the water might have become cloudy before doing anything to the water. Adding unnecessary chemicals and cleaners can upset your tank environment and harm your fish.
  2. Step 2 Add in good bacteria. 2 Add in good bacteria. Adding in good bacteria helps the natural processes of the tank. You can get good bacteria in the tank in a couple of ways. You can buy prepackaged bacteria from the store or buy gravel that has the bacteria already on it. You can also add gravel, rocks, driftwood, or a filter pad from an established tank to your own tank. It will have the bacteria on it.
    • Bacteria cultures will help to eliminate ammonia and nitrite, which are toxins. It changes them into less harmful nitrate, which is then removed during water changes.[1] The best bacterial species to do so are Nitrosomonas and Nitrobacter.[2]
    • To keep bacteria in the tank, avoid replacing the filter cartridges. Instead, wash the cartridges in old tank water.
    Advertisement
  3. Step 3 Place suitable live plants in the tank. 3 Place suitable live plants in the tank. Another way you can help keep your tank clean is by adding live plants. Live plants will help reduce nitrate levels. You can buy these at your local pet store.
  4. Step 4 Determine if you have the correct filter. 4 Determine if you have the correct filter. There are different filters that do different things for your fish. Cloudy water might be due to having the wrong filter. The filter you choose depends on the density of fish, the type of aquarium you have, and the use of live plants or artificial plants.
    • There are three different filters to choose from. Mechanical filters remove the particles by forcing the water through a material that catches the particles. Biological filters use bacteria to change toxins into less toxic substances. Chemical filters use chemicals to remove toxins or chemical from the water. Some filters use two or all of these methods.
    • Get the most powerful filter you can, but keep in mind that some fish such as bettas and hatchetfish won't tolerate a high flowing filter.
  5. Step 5 Stock your tank thoughtfully. 5 Stock your tank thoughtfully. When you are putting fish in the tank, don’t place too many in it. This can cause health problems and make your tank harder to clean. For goldfish a good rule of thumb is twenty gallons for the first fish and ten for every fish you add. Do research on the types of fish you want to get to determine what size tank they need.
    6. Advertisement
Method 2 Method 2 of 3:

Maintaining Your Aquarium

PDF download Download Article
  1. Step 1 Change the water. 1 Change the water. A good rule of thumb is to change 20% of the water in the tank every week.[3] If you use tap water, let it sit for two days after adding dechlorinator. This allows it to reach room temperature and let the pH settle, which helps the water not shock the fish when it is poured into the tank. The dechlorinator removes chlorine to minimize stress. You can also add a stress coat to the water, which can prevent diseases in fish.
    • You can also buy a device that hooks to your faucet that vacuums the gravel while removing and replacing water. You don’t have to wait a few days if doing it this way. Just make sure you make sure the temperature is close to your tank’s temperature and that you add in a chlorine remover.
  2. Step 2 Keep your filter clean. 2 Keep your filter clean. You must keep your filter up and running. The filter helps keep your tank healthy and prosperous, so neglecting it can lead to cloudy water or even fish death. Read the instructions for your filter to know how to take care of it.
    • All filters need to be examined weekly. Check them weekly for any blockages or build up. Clean as needed.
    • When cleaning the cartridges, use tweezers to remove fish waste or other blockage. Do not rinse the cartridges, as this removes bacteria that lowers the ammonia and nitrites. The bacteria will look brown when it grows on the filter.
    • Read the instruction manual that came with your pump to make certain it is properly installed and working as it should. The pump is important in aerating the aquarium with oxygen from the air. If it is not working properly the fish will suffer especially if the water is cloudy from waste matter.
    3. Advertisement
Method 3 Method 3 of 3:

Troubleshooting Cloudy Water

PDF download Download Article
  1. Step 1 Look for bacterial blooms. 1 Look for bacterial blooms. After changes to your fish tank, such as a large water change, a thorough cleaning, or medicating your fish, a bacteria bloom can occur. If this describes what led to the cloudiness in your tank, then be patient. The bacteria will balance out in a few days, and the water should clear on its own.[4]
  2. Step 2 Check your filters. 2 Check your filters. If your filters are not working properly, then the water can become cloudy. There is bacteria in your filtration system that consumes byproducts like ammonia and keeps things clean. If the filters stop working, the bacteria can build up in the water, making it look cloudy.
  3. Step 3 Adjust for additional fish. 3 Adjust for additional fish. If you had recently added new fish to your aquarium, make sure the tank set up can handle the additional fish. For example, if you just added a larger fish to a tank that had smaller fish, it might be too much for the filtration system. Add a different filtration system, or lessen the amount of fish in your tank.
  4. Step 4 Refrain from overfeeding your fish. 4 Refrain from overfeeding your fish. Overfeeding your fish can cause cloudiness in the water. Fish need to be fed sparingly. Feed them an amount of food once a day the size of their eye, and give them one or two fast days a week.[5]
  5. Step 5 Be mindful with decorations. 5 Be mindful with decorations. Sometimes, cloudiness can be caused by decorations. Make sure to wash all decorations carefully before adding them to the tank. Check all decorations in your tank to make sure they are designed for aquariums and purchased at good pet stores.[6]
    • Check for melting or misshapen decorations, softening or loosening decorations, or flaking paint or discolorations on decorations.
  6. Step 6 Control algae. 6 Control algae. Toxic blue-green algae clings to the sides of the tanks and sometimes to the decorative items in the tank. A good time to scrape algae from the sides is right before you change the water. Use a soft plastic squeegee or a clean toothbrush to gently scrape the side, then rinse under water to clean before taking another swipe. Remove all the ornaments and scrub in the old tank water to prevent shock in your fish.
    • Make sure your tank doesn’t get too much light because that can cause algae growth. Don’t place your tank close to a window and only keep tank lights on for 8 to 10 hours a day.[7]
    • It is important not to overfeed your fish, as leftover food can contribute to algae growth and an ammonia spike.
    7. Advertisement

How Do You Keep Aquarium Water Clear?

Expert Q&A

Search Add New Question
  • Question How do I make my fish tank water crystal clear? Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance. Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Expert Answer Your best bet is to avoid overfeeding your fish and do partial water changes at least once a week. Thanks! We're glad this was helpful. Thank you for your feedback. If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow Yes No Not Helpful 3 Helpful 8
  • Question How can I make my aquarium decorations safe? Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance. Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Expert Answer Choose decorations that are made for fish tanks. It's best to get them from a quality pet store. Be sure to wash the decorations before you put them into your tank because they can dirty the water if they're not clean. Thanks! We're glad this was helpful. Thank you for your feedback. If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow Yes No Not Helpful 1 Helpful 1
  • Question How do I know if I overfeed my fish? Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance. Craig Morton Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Expert Answer Your fish tank water may get cloudy. If you overfeed fish, the excess food will disintegrate in the water. Thanks! We're glad this was helpful. Thank you for your feedback. If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow Yes No Not Helpful 2 Helpful 3
See more answers Ask a Question 200 characters left Include your email address to get a message when this question is answered. Submit Advertisement

Tips

  • Rotting organic material is often the cause of bacterial blooms, which causes cloudy water. Remove anything dying/dead that in your tank. Thanks Helpful 0 Not Helpful 0
  • Do not overstock your fish tank or you will have a difficult time keeping it clean. Thanks Helpful 0 Not Helpful 0
  • A thorough cleaning of your tank—gravel, filters, décor, tank—along with draining all the water may be needed. But only attempt this after you have tried everything else, as this will shock your fish and probably kill most of them. Thanks Helpful 0 Not Helpful 0
Show More Tips Submit a Tip All tip submissions are carefully reviewed before being published Name Please provide your name and last initial Submit Thanks for submitting a tip for review! Advertisement

You Might Also Like

Lower Ammonia Levels in Your Fish TankHow toLower Ammonia Levels in Your Fish Tank Take Care of Your FishHow toTake Care of Your Fish Control an Algae BloomHow toControl an Algae Bloom Lower Your Nitrate/Nitrite Levels in Your Fish TankHow toLower Your Nitrate/Nitrite Levels in Your Fish Tank Clean Aquarium Filter Without Killing BacteriaHow to Clean Aquarium Filters without Killing Bacteria Do a Water Change in a Freshwater AquariumHow to Do a Partial Freshwater Change for Stable Water Chemistry Decrease Aquarium Algae NaturallyHow toDecrease Aquarium Algae Naturally Clean a Fish TankHow toClean a Fish Tank Keep a Goldfish AliveHow toKeep a Goldfish Alive Set up a Fish Tank (for Goldfish)How toSet up a Fish Tank (for Goldfish) Lower Ammonia Levels in a Fish Tank if They Are Not Very HighHow toLower Ammonia Levels in a Fish Tank if They Are Not Very High Add Fish to a New TankHow toAdd Fish to a New Tank Cycle a Fish TankHow toCycle a Fish Tank Reduce Chlorine in an AquariumHow toReduce Chlorine in an Aquarium Advertisement

References

  1. ↑ https://www.marineland.com/Information/Infographics-and-Guides/A-Beginners-Guide.aspx
  2. ↑ https://www.bioconlabs.com/nitribactfacts
  3. ↑ Craig Morton. Aquarium Specialist, CEO of Aquarium Doctor Inc.. Expert Interview
  4. ↑ https://www.fishtanktutor.com/how-to-get-rid-of-white-cloudy-aquarium-water
  5. ↑ Craig Morton. Aquarium Specialist, CEO of Aquarium Doctor Inc.. Expert Interview
  6. ↑ Craig Morton. Aquarium Specialist, CEO of Aquarium Doctor Inc.. Expert Interview
  7. ↑ https://www.pets4homes.co.uk/pet-advice/tips-on-keeping-fish-tank-water-crystal-clear.html

About This Article

Craig Morton Co-authored by: Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. This article was co-authored by Craig Morton. Craig Morton is the CEO of Aquarium Doctor Inc. based in Huntington Beach California and servicing Orange County, Los Angeles County, and the Inland Empire. With over 30 years of aquarium experience, Craig specializes in creating custom aquarium designs along with aquarium installation, service, and maintenance. This article has been viewed 262,894 times. 31 votes - 96% Co-authors: 15 Updated: July 4, 2025 Views: 262,894 Categories: Aquariums | Cleaning Aquariums Article SummaryX

To keep your aquarium water clear, change out about 20% of the water in the tank every week. If you use tap water, let it sit for two days so the chlorine can dissipate and the water can reach room temperature, otherwise, it may shock the fish. Check your water filter at least once a week for blockages, and clean or replace it once a month. Live plants may also help keep the water in your tank clear. Read on for advice from our veterinary reviewer on adding beneficial bacteria to your tank! Did this summary help you?YesNo

In other languages Spanish Italian Portuguese Russian French Indonesian Dutch Arabic Chinese Vietnamese Thai
  • Print
  • Send fan mail to authors
Thanks to all authors for creating a page that has been read 262,894 times.

Reader Success Stories

  • Anonymous

    Anonymous

    Jul 13, 2017

    "The whole thing was useful for someone like me who is doing it for the first time. I am learning slowly, at the..." more
More reader stories Hide reader stories Share your story

Did this article help you?

Yes No Advertisement Cookies make wikiHow better. By continuing to use our site, you agree to our cookie policy. Craig Morton Co-authored by: Craig Morton Aquarium Specialist, CEO of Aquarium Doctor Inc. Co-authors: 15 Updated: July 4, 2025 Views: 262,894 96% of readers found this article helpful. 31 votes - 96% Click a star to add your vote Anonymous

Anonymous

Jul 13, 2017

"The whole thing was useful for someone like me who is doing it for the first time. I am learning slowly, at the..." more Anonymous

Anonymous

Jun 4, 2017

"It was helpful to know that I need to be patient with the cloudy water and see if it fixes itself. I was worrying..." more Anonymous

Anonymous

Jul 23, 2017

"Frequency of feeding fish has caused the aquarium water to be come cloudy and out of control. I am going to reduce..." more Anonymous

Anonymous

Jul 25, 2017

"It is nice to know from this that the filter can be changed sooner if needed. Also, that it is safe to use tap..." more Anonymous

Anonymous

Dec 17, 2017

"Overfeeding was my problem. I liked that there was a specific instruction and that a day or two of fasting is OK." Share yours! More success stories Hide success stories

Quizzes & Games

Can You Spot The False Climate Claims QuizCan You Spot The False Climate Claims QuizTake QuizWhat Pet Should I Get QuizWhat Pet Should I Get QuizTake QuizDo I Smell Bad QuizDo I Smell Bad QuizTake QuizWhat Fish Am I QuizWhat Fish Am I QuizTake QuizWhat Skin Type Do I Have QuizWhat Skin Type Do I Have QuizTake QuizHow Disgusting Am I QuizHow Disgusting Am I QuizTake Quiz

You Might Also Like

Lower Ammonia Levels in Your Fish TankHow toLower Ammonia Levels in Your Fish TankTake Care of Your FishHow toTake Care of Your FishControl an Algae BloomHow toControl an Algae BloomLower Your Nitrate/Nitrite Levels in Your Fish TankHow toLower Your Nitrate/Nitrite Levels in Your Fish Tank

Trending Articles

Are You Unc? Discover How Old Your Vibe IsAre You Unc? Discover How Old Your Vibe IsTell That Your Crush Likes You BackHow toTell That Your Crush Likes You BackBe PrettyHow toBe PrettyWhat Emojis Mean Sex?What Emojis Mean Sex?Why Can't I Sleep QuizWhy Can't I Sleep QuizCat Sleeping Positions: 22 Common Poses ExplainedCat Sleeping Positions: 22 Common Poses Explained

Watch Articles

Impress a Girl on a First DateHow toImpress a Girl on a First DateWhat Are Tear Burns on TikTok and What Causes Them?What Are Tear Burns on TikTok and What Causes Them?Wear a HoodieHow toWear a HoodieChiffonadeHow toChiffonadeMake a Fabric RoseHow toMake a Fabric RoseConfront a BullyHow toConfront a Bully

Trending Articles

Gen Beta Slang QuizGen Beta Slang Quiz Wear the Clean Girl Aesthetic: Everything You Need to KnowHow to Wear the Clean Girl Aesthetic: Everything You Need to KnowCan We Guess How Many Exes You Have?Can We Guess How Many Exes You Have?What Does Your Rice Purity Score Really Mean?What Does Your Rice Purity Score Really Mean?130+ Sexy, Sweet, & Seductive Messages for Him130+ Sexy, Sweet, & Seductive Messages for Him Play the Concentrate Game (For A Little Scare!)How to Play the Concentrate Game (For A Little Scare!)

Quizzes & Games

Why Can't I Sleep QuizWhy Can't I Sleep QuizTake QuizWhat Brainrot Word Am I QuizWhat Brainrot Word Am I QuizTake QuizBedroom Aesthetic QuizBedroom Aesthetic QuizTake QuizWhat Kind of Reality Check Do I Need QuizWhat Kind of Reality Check Do I Need QuizTake QuizAm I Toxic QuizAm I Toxic QuizTake QuizWhat's the Best Meal Kit for Me QuizWhat's the Best Meal Kit for Me QuizTake Quiz wikiHow
  • Categories
  • Pets and Animals
  • Fish
  • Aquariums
  • Aquarium Maintenance and Repair
  • Cleaning Aquariums
wikiHow Newsletter You're all set! Helpful how-tos delivered toyour inbox every week! Sign me up! By signing up you are agreeing to receive emails according to our privacy policy.
  • Home
  • About wikiHow
  • Experts
  • Jobs
  • Contact Us
  • Site Map
  • Terms of Use
  • Privacy Policy
  • Do Not Sell or Share My Info
  • Not Selling Info
  • Contribute

Follow Us

×

Don’t miss out! Sign up for

wikiHow’s newsletter

Subscribe You're all set! X --630

Tag » How To Keep Fish Tank Clean