Best UV Sterilizer for Aquarium – Top 5 Reviews, Guide, FAQs & More

Table of Contents show

You’ll agree with us when we say that a UV sterilizer can be a valuable piece of equipment if you do your research and find the right one for your aquarium. 

Keeping this in mind, we decided to run some tests on all the UV sterilizers we could find in order to understand how they work and to separate the high-quality ones from the cheaply-built ones. 

Today, we’ll discuss how UV sterilizers work and how you can make an informed decision to bring one home that’s suitable for you.

Top Pick

This powerful UV sterilizer boasts a sturdy body and operates completely silently. You’ll find it goes for long periods without needing any kind of maintenance.

Runner Up

This is a heavy-duty product and can handle aquariums up to 75 gallons. It comes with a powerful submersible pump that helps circulate the water through it.

Also Great

Coming with all the tubings and fittings you need, this product is compatible with just about any aquarium. It’s external so it doesn’t take up any space in the tank.

We tested all the products under several different conditions and these three conclusively came out on top.

Now, let’s get into the reviews for the top 5 best UV sterilizers for aquariums. 

Best UV Sterilizers for Aquariums - Top 5 Reviews

1. All-Around Best UV Sterilizer for Aquariums - AA Aquarium Green Killing Machine Internal UV Sterilizer Review

This is a product we’d been hearing a lot about so we decided to put it through our most rigorous test. We used it to clear the water of one of our aquariums that had been infested with green algae. We let it run 24/7. We expected it to take at least a week if not more for it to completely clear out the water but to our surprise, it was able to turn our aquarium’s water crystal clear within 5 days. 

The filtration pump it comes with is powerful but also incredibly quiet. It does not disturb you or your fish in the slightest and once you turn it on, you won’t even remember it’s there.

Features of AA Aquarium Green Killing Machine Internal UV Sterilizer – Best UV Sterilizer for Aquarium

  1. Dimensions: 16 inches by 10 inches by 14 inches
  2. Weight: 1 pound
  3. Works at a power of 9 watts
  4. LED indicator for when bulb needs changing
  5. Low-voltage transformer
  • Comes with a 3-year warranty
  • Requires little maintenance
  • Easy to use
  • Easy to mount
  • Lightweight for its size
  • Takes up quite a lot of space inside the tank

If you want a reliable and fast-acting UV sterilizer, this is the product for you. It’s easy to handle and also quite user-friendly.

2. Best Inexpensive UV Sterilizer for Aquariums - SunSun JUP-01 9W UV Sterilizer Review

This UV sterilizer is fairly easy on the pocket but the level of performance it offers is nothing to laugh at. The pump that comes with it can circulate 210 gallons of water every hour and it’s appropriate for aquariums as big as 75 gallons. If you look online or in your local market, you’ll see that UV sterilizers that offer a similar level of performance are much more expensive than this product. 

It’s designed to be simple to mount. There’s no complicated setup or priming involved. You also don’t have to set any settings or adjustments when you first turn it on. All you have to do is plug it in and let it work its magic. 

Features of SunSun JUP-01 9W UV Sterilizer

  1. Dimensions: 12 inches by 3.3 inches by 3.75 inches
  2. Weight: 2 pounds
  3. Operates at a power of 9 watts
  4. Pump flow rate: 210 gallons per hour
  5. Suitable for aquariums up to 75 gallons
  • Footprint is relatively small
  • Highly effective
  • Easy to use
  • Bulb lasts longer than most of its competitors
  • Affordable
  • Flow rate may be too powerful in smaller aquariums
  • Heavy and bulky

If you can’t afford to spend a lot of money but still want an effective UV sterilizer then this is the product you’re looking for. It’s long-lasting and sturdy. 

3. Best Heavy-Duty UV Sterilizer for Aquariums - Jebao 36W Aquarium Koi Fish Pond UV Light Sterilizer Review

We tested this product on our Koi pond which had been experiencing an algae bloom. The manufacturer claims that you should install it between your filter and the aquarium for it to have the best results and that’s exactly what we did. This meant that the UV light was shining on filter water. 

Although the manufacturer claimed that the pond would become clear within 7 – 10 days, we were pleasantly surprised to see that our pond water became crystal clear within 6 days. 

We’ve been using this UV sterilizer for our Koi pond for months now and it has shown zero dips in quality or performance.

Features of Jebao 36W Aquarium Koi Fish Pond UV Light Sterilizer

  1. Dimensions: 20 inches by 13 inches by 4 inches
  2. Weight: 7 pounds
  3. Works at a power of 36 watts
  4. Maximum flow rate of 4400 gallons per hour
  5. Comes mostly pre-assembled
  • Operates silently
  • Requires very little maintenance
  • Extremely durable
  • Incredibly high level of performance
  • Easy to assemble and mount
  • Quite bulky and difficult to handle
  • Only suitable for ponds and extremely large aquariums

If you’re looking for an effective filter for your pond or large aquarium then this product is ideal for you. It’s cost-efficient and incredibly effective.

4. Best UV Sterilizer for Smaller Aquariums - GRECH CBG-800 5W UV Sterilizer Review

This is a UV sterilizer that’s perfectly suited for aquariums between 20 and 50 gallons. The only downside is that it comes with a filter so you’ll have to utilize the filter alongside the UV sterilizer as well. You can’t really install this product onto an aquarium that already has a filter mounted onto it. 

That being said, you’ll be satisfied with the performance of the filter and as for the performance of the UV sterilizer, it’s quite impressive. It has the lowest wattage UV bulb out of all its competitors and yet, it’s still able to eliminate all microorganisms inside your aquarium highly effectively and also very quickly. 

Features of GRECH CBG-800 5W UV Sterilizer

  1. Dimensions: 9.5 inches by 6.8 inches by 7.5 inches
  2. Weight: 3.6 pounds
  3. 5-watt sterilizer bulb
  4. Maximum flow rate of 211 gallons per hour
  5. Adjustable flow rate
  • Easy to assemble and disassemble
  • Easy to clean
  • Requires little cleaning
  • Quiet operation
  • Comes with a filter as well
  • Limits your options when it comes to a filter

If you’re looking for a UV sterilizer that could work well with a smaller aquarium then this product is ideal for you. It doesn’t take up too much space and shows its effects very quickly.

5. Best Saltwater UV Sterilizer for Aquariums - Coralife Turbo-Twist UV Sterilizer Review

This product is one that comes with a unique design that helps it stand out from the crowd. The unique twist design is really something that makes it visually appealing to the outside as well and functionally, it allows a much higher surface area of the water to get hit by the UV light so it’s much more effective at eliminating microorganisms. 

It’s also specifically designed to operate effectively with saltwater aquariums and there are unique aspects to its design which discourage salt buildup and clogging. 

The mounting brackets that come with it also make it extremely easy to install it onto your aquarium. 

Features of Coralife Turbo-Twist UV Sterilizer

  1. Comes in three sizes: for 125 gallons, for 250 gallons and for 500 gallons
  2. Unique twisting design
  3. Indicator light for when it’s operational
  4. Suitable for both freshwater and saltwater aquariums
  5. Mounting brackets included
  • Relatively inexpensive
  • Unique design enables increased exposure to UV light
  • Suitable for aquariums of many different sizes
  • Compact size
  • Quite lightweight
  • Does not come with a pump

If you’re looking for a dependable UV sterilizer for your saltwater aquarium then this product is definitely for you. It doesn’t take up a lot of space and it features a very smart design.

best uv sterilizer for aquarium

Buyers’ Guide

What is a UV sterilizer for aquariums and how does it work? 

A UV sterilizer is a filtration unit that has a UV bulb fitted into it. A UV sterilizer can be a submersible internal unit or it can also be an external non-submersible unit. It requires an air pump or powerhead or something similar in order to push the aquarium water through it. Inside, the water is passed through a tube where it is in direct contact with the UV light that’s emanating from the UV bulb inside. 

This UV light helps eliminate all kinds of different parasites, bacteria, viruses and other harmful microorganisms that may be present inside your aquarium. A UV sterilizer can also be particularly effective in eliminating algae from an aquarium. 

Thus, in this regard, a UV sterilizer can be quite invaluable because it helps to eliminate threats that you might not even realize are there. 

A UV sterilizer eliminates microorganisms by virtue of the effect that a UV light has on their cell framework. The UV light alters it until they are unable to function properly anymore. It also prevents them from reproducing. 

What are some benefits of having a UV sterilizer in my aquarium? 

The benefits of UV sterilizers are pretty clear; some of these benefits are: 

  • They help eliminate harmful microorganisms from your aquarium water. 
  • They help take care of algae blooms that may be occurring inside your aquarium. This helps prolong the period between water changes and also helps take a load off of your aquarium’s filter. 
  • It’s a great addition to household ponds as they are much more prone to harmful diseases and parasites. 
  • UV sterilizers can be used as an alternative to medication for certain sick fish inside your aquarium. 

What are some things I should think about before purchasing a UV sterilizer for my aquarium

Here are some things to keep in mind when going out to purchase a UV sterilizer for your aquarium: 

  • Internal or External? 

As we mentioned earlier in this post, UV sterilizers can be internal or external. Depending on the size of your tank and how much space you have outside it to work with, you’re going to have to make this decision. 

If you don’t want the inside of your aquarium to become crowded or if you think there’s already a lot of equipment inside it, then we suggest you go for an external UV sterilizer. 

If you don’t want a lot of equipment sitting around outside your aquarium and you feel that it will be difficult to hide, then we recommend you get an internal UV sterilizer. 

  • Flow Rate 

Just like an aquarium filter, a UV sterilizer also requires some sort of force that will help propel the water through the UV sterilizer. The rate at which water is propelled through the UV sterilizer is important to take note of because it has to be just right. If it’s too low, water won’t pass through your UV sterilizer adequately enough. If it’s too high then it would disturb your fish and create waves inside your aquarium that are too strong. 

A good rule of thumb is to have a flow rate that is four times that of the size of your aquarium. 

  • Price 

A UV sterilizer is definitely a secondary piece of equipment and we do recommend that you don’t go overboard when shopping for one. Always opt for one that does the job it’s supposed to do and doesn’t come with additional, gimmicky features. That being said, you should steer clear of counterfeits and cheap, generic products. Always buy from a reputable brand even if it costs you a little more. 

How do I install my UV sterilizer onto my aquarium

If you’ve installed an aquarium filter in the past, the installation of a UV sterilizer is pretty much the same. Most of them come with instruction manuals that you can easily follow to set it up onto your aquarium. Be careful when setting up submersible UV sterilizers that they haven’t been rinsed or washed with chlorinated water as chlorinated water can kill the nitrifying bacteria inside your aquarium. 

Once everything is properly set up, ensure one more time that all the tubings and wires are securely connected and then turn your UV sterilizer on. 

How do I maintain my UV sterilizer for my aquarium?

You should monitor and ensure that the quartz sleeve is clear and there’s no obstruction of any sort inside it. This is because any solid obstruction such as algae or debris sticking to it will block the UV light from hitting the water and thus, render the UV sterilizer useless. You can clean it using rubbing alcohol. 

Frequently Asked Questions (FAQs)

Are UV sterilizers effective in coral reef aquariums? 

Yes. UV sterilizers can prove to be a wonderful addition to coral reef aquariums. Corals are often plagued by microorganisms, parasites, and viruses that can be very hard to detect and even harder to eliminate. Installing a UV sterilizer can be a very smart way to neutralize any and all potential threats and help your coral reef aquarium thrive. 

How long should I leave my UV sterilizer on in my aquarium? 

This depends on the water conditions of your particular aquarium. If you have a particularly dirty or cloudy tank then we would recommend running your UV sterilizer 24/7 until it becomes clear. However, if you have a standard tank with relatively clear water then we recommend you only provide it with UV light for anywhere between 8 and 12 hours. 

Does a UV sterilizer kill ammonia in my aquarium? 

No. A UV sterilizer kills living beings such as bacteria, parasites, etc. Ammonia is a compound and needs to be broken down through biological filtration with the aid of beneficial nitrifying bacteria present inside your tank. If you’re having trouble with rising ammonia levels inside your aquarium then we actually recommend switching your UV sterilizer off as it could be killing off the beneficial bacteria inside your tank. 

Is a UV sterilizer safe for my fish? 

Yes. A UV sterilizer is utilized to control infections and eliminate harmful bacteria. If anything, it’s beneficial for your fish. UV light does not have any residual effect on your fish so you don’t need to worry about any unforeseen side effects. Just be sure the flow rate of your UV sterilizer is appropriate as too strong of a flow rate can definitely stress your fish out. 

Will a UV sterilizer kill Ich? 

A UV sterilizer will eliminate harmful microorganisms inside the water but it won’t be able to treat the adult stage of ich that is present on the bodies of your fish. Fish that are affected by Ich will need to be treated separately. 

How long do UV sterilizer bulbs last? 

Most high-quality UV bulbs last about six months. With proper care and a stable electric current, sometimes, they can last even more than that. 

When should I change my UV sterilizer’s bulb? How do I do it? 

You should change your UV sterilizer’s bulb when you start to notice that it’s dimming in brightness or if it starts to flicker. The changing process can vary depending on the make and model but it’s usually quite straightforward and the same as changing any standard light bulb. The important thing to note is that you should never look at a UV bulb directly when it’s on as it can cause quite serious damage to your eyes. 

Can UV light kill beneficial nitrifying bacteria in my aquarium? 

Yes. A UV light does not make a differentiation between good and bad bacteria, it simply eliminates all of them. This is not a cause for alarm though as your aquarium’s filter contains biological filtration media which is a breeding ground for beneficial nitrifying bacteria so they will constantly be produced there no matter what. 

However, if you’re cycling your aquarium initially then we strongly recommend that you don’t set up your UV sterilizer with it. Your UV sterilizer should only be installed after your tank has completely cycled. Otherwise, your UV sterilize will prevent the nitrifying bacteria from multiplying inside your tank. 

Can excessive UV light kill my fish?

Although generally, UV light is beneficial for fish, if you provide too much of it, it can definitely have harmful consequences. Excessive UV light can cause irreversible damage to your fish’s health such as retinal damage and damage to their embryos. 

How long does UV light normally take to clear green water?

This can vary highly depending on the size of your aquarium and the flow rate of your UV sterilizer but in general, a UV sterilizer will take anywhere between 2 days to a week to completely turn green water into clear water. Note that this needs to be accompanied by regular water changes as you need to get rid of the dead algae inside your aquarium as well. 

Final Verdict

UV sterilizers can be a very useful piece of equipment if you look into them properly and choose an appropriate one for you. 

After much deliberation, we had to go with the AA Aquarium Green Killing Machine Internal UV Sterilizer. For a product that’s so powerful, it works very quietly and its low price really does not reflect the high level of performance it offers. 

This brings us to the conclusion of our post for the best UV sterilizers for aquariums. 

Give us feedback and let us know what UV sterilizer you’re using for your aquarium.

You Might Be Interested In...

Leave a Comment

Your email address will not be published. Required fields are marked *