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The Best Aquarium Water Clarifiers for 2021

best aquarium water clarifier

One of the biggest problems that most aquarium owners have to deal with is cloudy water. Some say that you just need to wait for the dirt to settle. However, if you have been waiting for a couple of days and the water is still blurry, then you will need to use the best aquarium water clarifier.

A water clarifier is a solution that contains natural enzymes that cause a chemical reaction to the water. Clarifiers allow the solids suspended in the water to clump together, making them enough to get caught in the aquarium’s filter.

You need to be careful when choosing the best water clarifier for aquariums, though. The reason is that choosing the wrong product can potentially harm or maybe even kill your fish. To make sure that you will not be making a very expensive mistake, here is a short guide and a couple of suggestions that you may want to try.

Best Aquarium Water Clarifier Reviews

1. Aqueon Water Clarifier

aqueon water clarifier

I have used quite a lot of water clarifiers, but the Aqueon water clarifier is probably the fastest-working one. I have a small, 15-gallon, quarantine tank that always seems to have cloudy water. Just a couple of drops of this product and the water started to become clearer after just 10-15 minutes.

If you are wondering if this product will have an adverse effect on your fish and live plant, then the answer is no. I used this product numerous times with the fish in the tank and all of them are still healthy. The aquarium water clarifier ingredients are all relatively safe.

As mentioned earlier, you will need less than a capful if you are treating a 20-gallon tank. Note that you will also require less than that if you have a smaller tank. I have a small, 1-gallon goldfish bowl, and it only needed 3-4 drops to get the water to clear up considerably.

Do keep in mind that this is not a product that you can use to eliminate aquarium maintenance. Note that it will only make cleaning and maintaining the aquarium a whole lot easier. This is not a miracle product. You will still need to perform routine cleaning, though you do not have to do it as often as before.

Another nice thing about this product is that the cap already has markings so you will know just how much you will need. No more guesswork and risking overdosing on your tank. According to many Aqueon water clarifier reviews, the markings on the cap are quite accurate.

The thing that you need to keep in mind when using this product is that it is not suitable for treating algae bloom or bacterial bloom. It will only work on solid particles suspended in the water, like extremely fine dust and sand.

Pros
  • Clarifies the water quickly
  • Safe for fish and plants
  • Only needs a capful for a large aquarium
  • Makes aquarium maintenance a lot easier
  • The cap has useful markings to help with dosing
Cons
  • Will not work on algae or bacterial bloom

Remember that this product will never serve as a replacement for good aquarium maintenance. If you do not take proper care of your tank, the water will still get cloudy. Still, remember that for its intended purpose, this product does work exceptionally well. It can make the water in the aquarium crystal clear.

2. TetraPond Water Clarifier

tetrapond water clarifier

If you have ever owned a koi or turtle pond, then you know how fast they can make the water filthy. I have used this product for a couple of months and my pond is so clear that I can see the bottom. I do not know how other people fared with this, but my pond started getting clear after a day or two.

This is pretty strong stuff and it needs to be since it will be dealing with a lot of nasty stuff. However, if you follow the directions properly and you also consider the amount of water that is in your pond, then I think this product will not harm the fish and plants in your pond.

As an owner of an artificial pond, the thing that I hate the most about it is the bi-weekly cleaning schedule. This product made cleaning so much easier by making the dirt in the water clump up together to form a dense mass at the bottom. It is now just a matter of using a gravel cleaner to pick up the mess.

I use this product to help maintain my pond. If I do not use this, cleaning the water to prevent it from getting cloudy again takes a lot of work. There are even times when I need to replace all the water if it gets a bit too dirty. With its help, keeping my pond clear and clean is significantly easier.

Another thing to note about this product is that it is heavy-duty stuff. I have koi and turtles in my pond, and they make a lot of waste. With this product, the water remains clear and the ammonia levels are well under the safe amounts.

The only problem with this fish tank water clarifier is that if you use even a little too much of this product, it can be toxic to your fish. I would advise you to err on the side of caution and use a bit less than the amount stated in the directions. It would take a bit longer, but at least, you have an assurance that your pond inhabitants are safe.

Pros
  • Works in as fast as a couple of days
  • Clears the water without any adverse effects on the fish
  • Can work even on ponds with turtles and koi
  • Makes cleaning ponds so much easier
  • Viable pond maintenance option
Cons
  • Can kill koi and other fish if you use even a little too much

Keeping a pond clear and clean is hard work and you will need the strong stuff to make it look presentable. In that case, this product is what you need. You do need to be careful with the dosage, though. I suggest going easy on the stuff and do not be in too much of a hurry to see results.

3. Acurel Water Clarifier

acurel water clarifier

This water clarifier is an amazing product. You do not have to wait too long for the water to clear up when you use it. Just half an hour after I used this product on an extremely cloudy goldfish tank and I immediately noticed a huge difference in water clarity. After around three hours, the tank is so clear you would think the water was new.

This top fin water clarifier is made from all-natural resources so it is relatively safe to use on any freshwater aquarium. I also used this product on a tank with tetras and mollies and they were all fine. There were also a couple of snails and shrimp in the tank and they too were none the worse for wear.

As mentioned earlier, I have a goldfish tank, and I would often overfeed them as they are quite voracious eaters. The problem with overfeeding is that it would create a lot of waste as a result. Thankfully, this water clarifier for fish tanks helped keep the ammonia level in the water safe, so my fish are still healthy.

I use an overhead water filter and it is not the most efficient. However, after using this product, the filter could now filter almost all the dirt in the water. This product, through a completely biological process, makes the dirt clump together into larger particles, making them easier for the filter to catch.

What I genuinely liked about this product is that it significantly lessened the frequency of water changes. Before, I needed to partially replace the water every week, but after using this one, I do it once a month. There are even times when I would do it after two months.

Be warned, though. Even if it is a natural product, it is still a very potent substance. It might look like the dosage indicated in the directions will not be enough, but you should not put more than what is recommended as it could turn the water slightly toxic.

Pros
  • Clarifies aquarium water in hours
  • Can help prevent the harmful effects of overfeeding
  • Safe for all freshwater fish and invertebrates
  • Increases the efficiency of the aquarium’s filter
  • Makes your water so clear that it will always look fresh
Cons
  • Super concentrated and easy to use too much

This product is one of the most effective water clarifiers I have ever had the pleasure of using. If you want to keep your aquarium looking clear and clean, then this is the thing for you.

4. Aquarium Water Clarifier Algone

aquarium water clarifier algone

If you have more than one type of aquarium, then you do not need to buy separate products for each one. This water clarifier is usable on both freshwater and saltwater aquariums, as well as outdoor ponds with a filtration system. This works equally well in any aquarium setup.

Unlike other water clarifying products, this one can clear up algae blooms as well. I made a mistake in placing one of my tanks in a place where it gets around 1-2 hours of direct sunlight, and I constantly need to deal with algae. This product helped me maintain the clarity of the water until I found another space for the tank.

In addition, it can eliminate nitrates and ammonia from the water. This is important if you own fish that produce a lot of waste. I have a tank with a couple of goldfish, and this filter pouch not only helps keep the water clean, but it also eliminates the toxic nitrates and ammonia from the fish waste.

I find that this is the easiest to use among all the water clarifiers I have used so far in my years of owning an aquarium. I do not have to worry about putting too much or too little of a product. I just needed to place the filter pouch inside the filtration system and it will start working on its own.

You will be getting three packs containing six pouches each, and this is actually enough for more than three years’ worth of use. One pouch can last up to three months. However, just to be sure, I replace the pouches every two months and it is still enough for at least two years of clear water.

Speaking of filtration systems, these filter pouches are tiny, so you may need to use more than one if you have a larger filter system. I have a regular-sized box overhead filter so just one pouch is enough.

Pros
  • Usable in freshwater and saltwater aquariums – You can also use it in freshwater ponds
  • Inhibits algae bloom
  • Can remove nitrates and ammonia
  • Easy to use
  • Each filter pouch can last for 3 months
Cons
  • These filter pouches are small, so you might need to use more than one for bigger filter systems

This product is ideal for beginners as there is no measuring needed. Each pouch contains exactly the right amount of ingredients so that the water will always be crystal clear.

5. API ACCU-CLEAR Water clarifier

api accu-clear water clarifier

In my experience, this product works quite fast. It may not be as fast as the other products I tested, but not bad overall. Every time I use this product, it takes no more than two days for the water to turn crystal clear. Even though it is not the fastest, it is still a reliable water clarifier.

This product works by gathering all the suspended dirt and other solid particles accumulated in the water. This allows the filter to work more efficiently. Because all the dirt clumped together, even a regular filter medium will be able to pick them all.

I am using this product on one of my tanks for weekly maintenance. I do not use quite as much of the stuff for keeping my tank clear. This product makes the filtering system do most of the cleaning tasks. I do not need to clean the glass and gravel quite as much now because this product makes the filters more efficient.

I was surprised at first when I saw how tiny the bottle that this product came in, but after a couple of weeks of use, I barely used a third of the contents. This stuff is potent and you will only need a couple of milliliters for a 15–20-gallon tank. That tiny bottle can go a long way.

It also helped me save a lot of money. Thanks to this product, I no longer needed to change the water weekly. Now, I only need to do partial changes every month or so. I have a 100-gallon tank, so even partial water changes weekly can be quite expensive.

I have seen a lot of customer reviews saying that it only made the water worse. Either the reviewers had algae bloom in their tank, or their filter systems are not up to snuff. Although the water does get cloudier, note that it is also a sign that the product is working.

Pros
  • Works quickly – You can expect significant results in a day
  • Maximizes filter efficiency
  • Makes weekly maintenance easy
  • A little goes a long way
  • Makes water replacements less frequent
Cons
  • Makes the water cloudy before it clears up

You need to have a bit of patience when using this product. A lot of people said that this was no good because it made their water even cloudier. However, that is the sign that the product is working.

6. Carib Sea Aquatics BioMagnet Clarifier

carib sea aquatics biomagnet clarifier

This product is definitely among the top 5 fastest working water clarifiers I have tested so far. After roughly an hour of dosing a really cloudy goldfish tank, the water was already significantly clearer. A couple more hours passed and the water was so clear that the fish seemed to float in mid-air.

Another thing I liked about this product is that you will only need a little bit to treat a huge tank. The goldfish tank I used this on contained roughly 30 gallons of water, and I only needed slightly under a capful to get the water clear. This product comes in an 8-ounce bottle so I reckon it will last a while.

Keeping the water clean is a challenge when it comes to a goldfish tank, but this water clarifier makes it look easy. I put around half a cap of the product in the tank every week (sometimes two), which saved me from having to give weekly water changes. I now change the water one or two times a month.

I find that this works best on aquariums that use sand substrates. If you have always wanted to use fine sand as a cover for the bottom of your tank, use this one to keep the water from getting cloudy. I have a small tank for bettas that uses river sand as a substrate, and this water clarifier tetra keeps the water clear.

Another nice thing about this product is that you can use it on both saltwater and freshwater tanks. I have a small, 20-gallon saltwater tank and I also use this product on it. I discovered that it works well on it.

This product is very concentrated so you need to be careful when dosing your tank. It is easy to put too much and turn the water toxic. If you will be using this product in a tank with highly sensitive fish, then I suggest that you use slightly lesser doses than stated in the instructions.

Pros
  • Works quickly – You can even get noticeable results in an hour
  • Only needs a little bit of product to treat a large tank
  • Significantly lessens the frequency of water changes
  • Works best on aquariums that use sand as a substrate
  • Usable in both freshwater and saltwater tanks
Cons
  • Easy to overdose your tank

This product is suitable for both beginners and experienced aquarium owners. However, if you are a beginner, then you need to follow the instructions down to the letter to keep your tank healthy.

7. CrystalClear OneFix Water Clarifier

crystalclear onefix water clarifier

The thing that I liked the most about this product is that it does not contain any harsh chemicals. It uses natural bacteria to get rid of any dead organic materials that are suspended in the water, which is one of the biggest reasons why pond water turns cloudy.

I do not have a particularly large pond. It is roughly 50 square feet in size and only needed a 1/3 of a cup of this water clarifier. I was left with enough of the product to maintain my pond for the next six months or so. I use around ¼ cup of water clarifier every two weeks to keep the water clear.

Another neat thing about this product is that it starts working the moment it hits the water. After an hour or so, I already noticed significant improvements in the water quality of my pond. After a day, I can already see the bottom, which is a far cry from what it was the day before.

The bacteria in this product consume the waste that the fish produce, which means that it also helps keep ammonia levels down to almost zero. I closely monitor the ammonia and nitrate levels of the pond every week, and I have yet to get results that I need to be concerned about.

This product is also safe for use in any kind of aquarium. I use this in a tank that contains shrimp and snails, and they are still perfectly healthy. So, if you have a tank that contains a mix of different creatures, you can use this clarifying product on it.

A lot of people complained that this product did not work for them, and the reason is that they thought that this could also work on algae blooms. It is not meant for getting rid of algae, so you will need to get a separate product for dealing with that.

Pros
  • Uses natural bacteria to clarify the water
  • The entire bottle is enough to treat up to 12,000 gallons
  • Works the moment that it hits the water
  • Keeps ammonia levels down
  • Safe for all kinds of aquatic creatures
Cons
  • Does not work on the algae bloom

Here are the things that you need to keep an eye out for when you are shopping for an aquarium water clarifier:

What to Look For When Buying a Aquarium Water Clarifier

aqueon water clarifier reviews

Here are the things that you need to keep an eye out for when you are shopping for an aquarium water clarifier:

Ease of Use

This is especially important if you are a beginner at keeping aquariums. As much as possible, do not use products that require you to mix components. The reason is that such products need precise measurements so there is a good chance that you might overdose on your tank.

Get the ones where you can just use the cap to measure the amount of product that you need to use.

Safety

This is the most important factor you need to consider. What use is a clear aquarium if your fish are all dead? You need to use a water clarifier that is safe for fish, live plants, and even invertebrates.

Just to be on the safe side, use a bit less than the amount mentioned in the instructions. It is better to just wait a little longer for the water to clear up instead of killing your fish because you got impatient.

Working Time

It would be nice if the water clarifier worked quickly, but it should not be your top priority. Many products work in just an hour, but I suggest that you get the water clarifier that works a bit more gradually. This is to guarantee the safety of your fish.

Added Benefits

Aside from making the water clear, it is also advisable for you to get a product that provides other benefits. For instance, many brands of water clarifiers also provide nitrate and ammonia removal. This type is actually more cost-effective since you will be getting three products and benefits in one package.

Frequently Asked Questions

best water clarifier for aquariums

How Long does a Water Clarifier Work in a Fish Tank?

The length of time needed for the water to clear will depend on the product itself and the size of the aquarium or pond. For instance, a small 10-gallon aquarium may only take one or two hours to clear, while a 100-gallon tank may take a day or two.

Some brands of water clarifiers also promise clear water in just an hour while others say it will take a couple of days. Also, because water clarifiers only make the suspended solids in the water clump together, it is up to the aquarium filter to pick up the dirt and make the water clear.

How Often Should I use an Aquarium Water Clarifier?

Since most aquarium water clarifiers are relatively safe, you can use them whenever you notice the water getting cloudy again. Moreover, you can use it to maintain your aquarium. Typically, you can put maybe half of the usual amount every week to prevent the water from getting cloudy again.

Conclusion

The reason why people keep aquariums is that they want to watch the fish swim graciously in the water. If the water is cloudy and murky, then it defeats the purpose of having an aquarium. If that is the case, then you will need the best aquarium water clarifier.

A good quality water clarifier will keep your aquarium looking clean all the time, which also means you will not need to replace the water as often as you did before. This will make keeping an aquarium a lot more enjoyable and less of a hassle.

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