7 Best UV Sterilizers for Guppy Aquariums

Best UV Sterilizers for Aquariums

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If you own a nice fish tank, or you plan to buy one, you will need to clean the water regularly. This is a standard requirement, no matter what type of fish you have inside the aquarium.

A standard water filter is a great device that will clean your tank, and leave a crystal clean water for your fish. However, there is something else you can add to your tank, to ensure an even better and healthier environment for your marine life.

Yes, a UV sterilizer. Why would you need such a device? This article will answer the question. But before doing so, let’s take a look at the best UV sterilizers you can get online. Any of these can easily be found on Amazon.

Once we talked about these items, you’ll find out what makes a UV sterilizer a good addition to your tank, we’ll talk about the benefits that come with using such an item; and if such a device is totally safe for your fish that live there.

1. Coralife Turbo-Twist UV Sterilizer

This is the first product that we’re describing in this article. It comes in 3 different versions, all for different needs. Right now, I’m talking about the first out of the 3, the 3X version. For a basic tank, that needs simple UV sterilizing, it will do very well.

It was designed to remove unwanted free floating algae from the tank, but not only. Besides algae, it will also get rid of all kinds of parasites and bacteria that might harm your fish, or carry diseases.

The twist-flow design that they used, allows for an increased exposure to UV light, which means better results in your aquarium. You can use it with fresh and salt water as well, and all sorts of fish and sea life.

It comes with mounting brackets, that will let you easily install the device 2 different ways: as an in-line sterilizer or hanging it on the side of the tanks. You can choose freely which set-up works better for your personal case.

Also, it’s worth mentioning, you can use this sterilizer with fish tanks, up to 500 gallons in volume. That is more than most people have, so it will surely stand up to your requirements.


2. Aqua Ultraviolet Advantage 2000+

This device is somewhat different from the previous model I talked about. In what way? For instance, this one is suitable not only for traditional aquarium, but you can use it with small fish ponds as well.

It’s slim and lightweight design make it a popular choice among beginner fish enthusiasts. This means that if you haven’t ever used such a device before, you’ll easily get the hang of it. Installing it is basically child’s play.

Its design was also influenced by the need to create a device that will result in 100% efficiency. This means that the UV light used by this sterilizer, will offer maximum effectiveness against all sorts of algae, parasites and bacteria that would otherwise hurt or sicken your fish.

Clearing the water from these particles, will usually be done in about 3 to 5 days. However, that’s not a rule. There were occasions when the Advantage 2000+ cleaned a tank from alga and parasites during a single night.


3. OASE Indoor Aquatics Claytronic 7W

This device is a top-notch product, that we highly recommend for both beginners and experienced fish owners. The Claytronic was created to promote clear water and healthy fish in any personal aquarium.

It works on achieving this goal, by using efficient technologies, to get rid of parasites, bacteria and algae, that could cause harm to your marine life. It works with both salt and fresh water tanks. It will prevent diseases and other health issues in your tank, by destroying the above mentioned particles.

Changing the UV light is easily done using the quick-release function built into the device. It also comes with an indicator that will let you know about your bulb’s effectiveness, without the need to open up the whole unit for a check.

Besides eliminating algae, it will also clear your tank from cloudiness caused by various particles, algae as well. The resulted water will be much clearer and healthier for your fish that live there.


4. Oxyfuel 18W Sterilizer

The Oxyfuel is a product that works from the outside of your tank. It stabilizes the water environment by removing even the toughest grime in your tank. It works in salt water reef set ups, fresh water aquariums and outside small fish ponds.

Besides killing the unwanted algae surplus in your tank, it also makes sure to keep the nitrate levels in the water at bay. This is very important, because fish are allergic to nitrates, and they can die if the concentration in the water is too high.

When the sterilizer works in sync with your water filter, it will result in much cleaner and clearer water. Also, the powerful UV light bulb, will prevent harmful bacteria from spreading in your aquarium. This way, you won’t have to use chemicals to get rid of these particles, which process could again harm your fish.

This sterilizer is made to work with huge aquarium or fish ponds. How big? You can successfully make use of this device, even with a tank that’s up to 6604 gallons in volume. Yes, that’s right!


5. AA Aquarium Green killing Machine Internal UV Sterilizer

This really is a killing machine. It kills every harmful bacteria and algae in your tank. The result is a beautiful clear water environment that your fish can enjoy. It eliminates cloudiness that appears due to a surplus of algae in the aquarium.

This device is actually among the most popular items sold in this category of products. Since that’s the case, you can be sure to use it effectively in your own tank as well.

It was created, so that you’d never have to touch the glass, because of the patented sealed UV light bulb. Chambered assembly means that you never have to touch the bulb itself, and the water dwell time also increases significantly.

You require no tools to complete the installation. The whole process will take no longer than 10 minutes. Just follow the easy steps described in the user’s manual, and the device will be ready for use in no-time.

A 3-year warranty is added to the pack as well, which is more than most other companies will offer for the same money.


6. SunSun JUP-01 9W UV Sterilizer

This item is best for those who own a medium-sized tank, of about 50 to 75 gallons. It allows you to control the spread of harmful microorganisms in your aquarium, by killing these particles effectively.

It comes with a submersible pumping unit, that works from inside the tank, and filters the water mechanically, by absorbing the floating debris from the water. This will help get better results, while the UV light bulb clears the water from all harmful bacteria, algae and parasites, that could kill your fish eventually.

It works with fresh water aquariums, like most people have. But besides that, you can also use it with outside fish ponds, or even salt water fish tanks, where algae can spread even quicker. It has a flow rate of 210 gallons per hour, meaning that a medium sized fish tank will be cycled more than twice during this time span.


7. Coralife Bio Cube UV Sterilizer for Aquarium, Mini

If all you need is a small UV light bulb, to help you clean the tank from remaining algae and parasites, the Bio Cube Mini is a great choice. Not everyone needs the other, more fancy items I listed already.

This small device will do basic water filtration, by using its UV light bulb to clear the water. You can use it with smaller fish tanks, which is recommended. However, even tanks up to 32 gallons can be sterilized using this little gadget.

The manufacturer recommends this item to be used with small fish tanks, that only contain relatively small quantities of water. This way, you can ensure a better performance from this device, while still making sure it will last a long period of time.


Now that you learned about all products, it’s time to see what are some benefits that come with using a UV sterilizer in your fish tank:

Benefits of Using UV Sterilizers in Aquariums

Among these benefits, we should start with an obvious one that is actually the most important: it results in a healthier environment for your fish to thrive in. This is the most important factor that people consider when buying a UV sterilizer.

It’s true, a traditional water filter will do a lot of good in your tank. However, if you use it in conjunction with a UV sterilizer, the results will speak for themselves.

Now, let’s break this down into multiple benefits:

  1. Kills harmful algae: the radiation given off by the UV light, will prevent the algae spores from reproducing in your tank, thus resulting in their death. This way, your tank will get much clearer, and also healthier for your fish.
  2. Kills parasites and bacteria that could affect your fish’s health: just like before, the radiation prevents parasites and bacteria too from reproducing in the aquarium. This way, they will disappear, and leave a healthy tank, where your fish can thrive and live long and happy lives.

A UV light has another benefit for your tank as well. There are certain microorganisms that your chemical filtration system won’t kill. And not even the bio-filter you placed inside your tank will do any difference.

In this case, a UV sterilizer can come in handy. Almost nothing can stand a long exposure to UV light. This is why even very tough bacteria or parasites will be killed, if you set up a UV sterilizer alongside your tank.

But if that’s the case, maybe you’re asking yourself if UV lights will kill beneficial bacteria too?

Does UV Sterilizer Kill Beneficial Bacteria?

If you don’t take precautions, then your UV sterilizer might actually kill beneficial bacteria too. That’s a fact. So, what can you do about this? It’s quite simple actually.

To prevent your UV sterilizer from killing beneficial bacteria in your tank, it’s a good idea to set up feeding ground for these bacteria far away from the light. For instance, you could place rocks on the bottom of the pond or aquarium, to prevent UV light from harming beneficial bacteria that live on the bottom of the tank, in the gravel.

Another idea would be to place a sand filter inside your tank, where the UV light can’t penetrate. This way, the bacteria that will live inside it, will be protected from the harmful light of your sterilizer.

How Long Does the UV Lamp Last in a UV Sterilizer?

The answer to this question mostly depends on the light bulb placed inside the device. There are many different version manufacturers use to build these products. Some of them are stronger, and break only after long period of use. Other are not that tough, and you might need to change them quite often.

However, a standard period of use for a UV lamp, is about 9000 hours, give or take. As I said above, this number can fluctuate, depending on the quality of the build. But generally, you can expect about 9000 hours of working time from a UV light bulb. That is about a year of functioning.

There is another factor that comes into play, when we think about this matter. How often do you use the sterilizer? Is it functioning all the time, day and night? If yes, then you can’t expect it to work efficiently longer than about 9000 hours.

However, if you only use it once in a while, to clean your tank better, the light will stay working for more time of course.

Is UV Sterilizer Safe for Fish?

This question arises naturally, since I just said that UV lights can kill beneficial bacteria, if you don’t prevent that from happening. So, what’s the matter with fish? Usually, a UV sterilizer is safe for you fish, if you use it cautiously.

How? It is recommended to not keep the device running at all times. It’s best to only plug it into the wall, when you need to clear the water better, or when you want a better result from your water filter unit.

To use it efficiently, and still cautiously, it’s best if you set out specific times when you’ll use the device. For instance, you could use it every 3rd day, to keep your aquarium in a quality state. While the sterilizer isn’t working, the normal water filter will do its job just as good as before.

Keep in mind this: if you don’t use the UV sterilizer with caution, yes, you could harm your fish. That is why there are certain precautions you need to take, when using such a device. Usually, these are written in the user’s manual of the device you just bought.

After all, UV light is dangerous and cancerous, but only if you use it the wrong way. That’s why you must always know what you’re doing, and obey the rules set out by the manufacturer.


In this article we talked about UV sterilizers and why they could be a needed addition to your fish tank. You learned what it means to use such a device in your own tank, and how to do it properly.

Also, we now know that UV light could be dangerous, so you need to use it cautiously, to not harm any of your sea life.

I listed and talked about the best products you can find on Amazon, if you think you need such a device.

Keep in mind, any of the products can prove to be an efficient sterilizer for your tank. But to make sure that is the case, you need to make the right decision.

Before deciding on a product, you must know the volume of your tank. This is the most important factor that comes into deciding which product is best for you. As you can see from above, certain items work with large fish tanks and small ones just as well. Others, not so much.

That is why you must consider your tank’s size before buying a product. This way, you’ll surely make a good decision, that will positively impact your aquarium.

Updated: November 27, 2019
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