7 Best UV Sterilizer Aquariums for Freshwater and Saltwater

Best UV Sterilizer Aquarium

Anyone with an aquarium knows how important filtration is to keep the system clean. However, there is one thing that aquarium filters cannot get rid of and that is microorganisms.

These very small creatures usually give the water a greenish color and occur as a result of external factors such as contaminated water and decomposing the fish food on the tank bed.

The only way to deal with them is by using a UV sterilizer, which is basically a UV light bulb that produces harmful light to the microorganisms. This results in cleaner and clearer water, which is good for the fish and good for clearer views of the tank as well.

Therefore, it is necessary to get the best UV aquarium sterilizer and this article looks at some of the best ones to consider in the market.

You can also read other product reviews of aquarium filter, aquarium pump, protein skimmer, CO2 diffuser

7 Best UV Sterilizer Aquariums – Reviews

Product Name




Current Price

1. AA Aquarium Green Killing Machine UV Sterilizer with Power Head

AA Aquarium Green Killing Machine UV Sterilizer with Power Head

9-watt UV sterilizer with a slow zigzag flow for more effective sterilization and includes a premium sponge for additional mechanical filtration  


2. SunSun JUP-01 9W UV Aquarium Sterilizer

SunSun JUP-01 9W UV Aquarium Sterilizer

Affordable UV sterilizer with a fast 210 GPH flow rate and a 9 watt UV light for doing the actual sterilization.  


3. AquaTop UVCP-13 Submersible UV Aquarium Sterilizer

AquaTop UVCP-13 Submersible UV Aquarium Sterilizer

Powerful UV sterilizer with the capability to handle up to a 2377-gallon tank due to a fast 528 GPH flow rate and a 13-watt UV light


4. Sun 13W Adjustable UV Aquarium Sterilizer

Sun 13W Adjustable UV Aquarium Sterilizer

13-watt UV sterilizer with a flow adjustment dial and comes with a flow regulating nozzle to give you complete control over the unit’s flow rate.


5. AquaTop IL10UV In-Line UV Sterilizer

AquaTop IL10UV In-Line UV Sterilizer

In-line UV sterilizer with a UV-C light bulb and can be installed along the return lines of a canister filter


6. Aqua Ultraviolet UV Aquarium Sterilizer

Aqua Ultraviolet UV Aquarium Sterilizer

Expensive aquarium sterilizer with a 25-watt UV light to treat freshwater at a rate of 1200 GPH and saltwater at a rate of 400 GPH


7. Coralife 77070 3X Turbo Twist UV Sterilizer

Coralife 77070 3X Turbo Twist UV Sterilizer

In-line aquarium UV sterilizer with a 9-watt UV light and is available in 3 different sizes


1. AA Aquarium Green Killing Machine UV Sterilizer with Power Head

AA Aquarium Green Killing Machine UV Sterilizer with Power Head
  • Fits: Up to 50 gallons
  • Power: 9 Watts
  • Flow rate: 50 GPH

AA Aquarium’s UV sterilizer is also named the green killing machine because it emits a 254nm wavelength UV light that is very effective at eliminating the green cloudiness caused by bacteria, mold, yeast, and pathogens.

On top of this, the unit features a premium sponge for filtration of dirt and debris, resulting in crystal, clear water that is perfect for the fish to grow.

The sterilizer is run by a moderately fast pump that circulates the water at a rate of about 50 gallons per hour, but this speed is reduced by the zigzag flow within the UV bulb.

This slow movement ensures that the water is screened thoroughly as it passes through the UV filter for a more effective green killing process.

In terms of compatibility, this unit can effectively sterilize aquariums that do not exceed 50 gallons in capacity. It is also compatible with both tropical and saltwater fish tanks, which makes it quite versatile.

Installation and maintenance are also quite simplified due to the presence of suction cups for attaching to the aquarium wall and an LED replacement notification for showing whether the UV bulb requires replacement.   


  • 254nm wavelength UV light for effective elimination of microorganisms
  • Premium sponge for mechanical filtration
  • Slow water flow for more effective sterilization
  • Compatible with fresh and saltwater tanks
  • Easy to install


  • Might take a long time to clear the cloudiness in a big tank because of the relatively slow flow rate. 
  • Only suitable for small aquariums

2. SunSun JUP-01 9W UV Aquarium Sterilizer 

SunSun JUP-01 9W UV Aquarium Sterilizer
  • Fits: Up to 75 gallons
  • Power: 9 Watts
  • Flow rate: 210 GPH

SunSun’s JUP-01 is the most affordable UV sterilizer in this review but don’t think it is a low-quality product.

For starters, the product has a 9-watt UV bulb, which is very effective at eliminating harmful microorganisms and free-floating algae from the water.

A built-in pump circulates water through the sterilizer at a rate of 210 gallons per hour while a big pre-filter sponge captures the dirt and debris so as to increase the surface area of the water that the UV light can penetrate through.

Installation of the sterilizer is simplified by the use of suction cups, which make it possible to attach the unit to the aquarium wall. It can be installed in either a vertical or horizontal orientation and being submersible, it requires no tubing before use.

The unit can be used to treat fresh and saltwater aquariums, as well as ponds of up to 75 gallons in capacity. This means that you may need two or more of this product for large-sized fish tanks.

An important thing to note here is that the UV bulb is recommended to be changed every year so as to maintain optimum sterilization.  


  • Affordable
  • 210 GPH built-in pump
  • Mechanical filter included for removing dirt and debris
  • Easy to install.
  • Can be used on fresh and saltwater tanks, and ponds


  • Not ideal for large tanks
  • The flow rate is not adjustable

3. AquaTop UVCP-13 Submersible UV Aquarium Sterilizer 

AquaTop UVCP-13 Submersible UV Aquarium Sterilizer
  • Fits: Up to 2377 gallons
  • Power: 13 Watts
  • Flow rate: 528 GPH

AquaTop’s UVCP13 is the kind of UV sterilizer that you would want if you have a really big tank because it is designed to handle up to a 2377-gallon aquarium.

In order to handle such a big capacity, the unit has a powerful pump that circulates water at a rate of 528 gallons per hour. This is quite fast and makes it possible to circle through all the water in a 2377-gallon tank in less than 5 hours.

Additionally, a more powerful 13 watt UV light bulb is used so as to provide more microorganism killing power in the fast flowing water while a foam filter is used to get rid of dirt and debris from the water before going through the UV light for more effective green killing.

Apart from freshwater use, this power makes it one of the best aquarium UV sterilizer for reef tanks because normally, these marine tanks are required to be big in size.

However, being a submersible unit, the strong motor might generate a lot of heat inside the tank while its lack of a mesh screen on the intake means that it can swallow small fish. With careful monitoring though, this won’t be a big problem.


  • Ideal for small to big aquariums
  • Fast 528 GPH flow rate
  • 13 watt UV light bulb
  • Foam filter for mechanical filtration
  • Usable on both marine (reef) and freshwater tanks


  • Might cause an increase in temperature inside the tank
  • Can swallow small fish

4. Sun 13W Adjustable UV Aquarium Sterilizer 

Sun 13W Adjustable UV Aquarium Sterilizer
  • Fits: Up to 150 gallons
  • Power: 13 Watts
  • Flow rate: 211 GPH

Sun’s aquarium UV sterilizer is quite unique due to its adjustability feature. On the outlet, the water flow can be controlled using an adjustable flow regulating nozzle that this product comes with.

Most importantly, a round knob on the sterilizer’s body can be easily turned to adjust the flow rate, which reaches a maximum of 211 gallons per hour.

This makes it probably the best submersible aquarium UV sterilizer because, with an adjustability function, you can slow down the water flow inside for an extended exposure time to the UV light so as to kill more microorganisms in extremely cloudy waters.

Apart from this, the unit features a foam filter for clearing out dirt and debris before passing the water through a 13-watt UV bulb for killing the bacteria that cause the cloudiness.  

A built-in 8-watt pump runs the entire system, giving the sterilizer a combined rating of 21 watts. This motor is strong enough to make the unit capable of handling up to a 150-gallon aquarium.

The only issue with this motor is that it is not very durable but a 30-day warranty will cover you at least for a few days.


  • Adjustable flow control using a dial and a nozzle accessory
  • Max flow rate of 211 GPH.
  • 13 watt UV light
  • Built-in pump.
  • Can handle up to a 150-gallon aquarium


  • The pump is not very durable
  • Very short warranty period

5. AquaTop IL10UV In-Line UV Sterilizer

AquaTop IL10UV In-Line UV Sterilizer
  • Fits: N/A
  • Power: 10 Watts
  • Flow rate: 211 GPH

This aquarium sterilizer is designed for in-line use, which means that it is not waterproof and thus, special care needs to be taken to ensure that it does not submerge into the water.

However, being an in-line sterilizer means that it does not occupy space inside the aquarium and thus, can be used to sanitize water for the smallest of fish tanks.

This makes it the best freshwater UV aquarium sterilizer because these tanks are usually available in smaller sizes compared to marine tanks.

On matters installation, this unit does require some piping, but it is a perfect addition for traditional canister filters. It can be simply attached to the piping coming out of such filters so as to sterilize the water before getting back to the tank. This makes its installation much easier.

Disinfecting is done using a 10-watt UV bulb that produces UV-C light, which is also known as germicidal-grade UV light. An additional UV-C lamp is included as an accessory for replacement when the current one dies out.


  • Does not consume space inside the aquarium
  • Can be installed as an addition to a canister filter
  • 10 watt UV-C light bulb
  • Comes with an additional UV-C lamp for replacement purposes


  • Requires piping
  • Not waterproof

6. Aqua Ultraviolet UV Aquarium Sterilizer 

Aqua Ultraviolet UV Aquarium Sterilizer
  • Fits: Up to 1200 gallons
  • Power: 25 Watts
  • Flow rate: 1200 GPH

This Aqua unit is the most expensive as well as the top-rated UV aquarium sterilizer in this review because of a couple of reasons. For starters, it can handle sterilizing both freshwater and saltwater aquariums but in different capacities.

For freshwater, the product can handle up to a 1200-gallon tank at a flow rate of 1200 gallons per hour while for saltwater, it can only handle up to a 150-gallon tank at a flow rate of 400 gallons per hour.

The unit features a 25-watt UV bulb, which consumes quite a lot of energy, but is necessary for coping with the fast flow rate. At least it ensures that the water passing inside has been greatly exposed to this germ-killing light.

In terms of installation, this sterilizer requires an in-line fitting and can either be installed as a separate unit or as an addition to a very powerful canister filter.


  • Compatible with both freshwater and saltwater aquariums
  • Can handle a maximum of a 1200-gallon fish tank
  • A top flow rate of 1200 GPH
  • 25-watt UV sterilizer bulb
  • Requires an in-line installation, which means it does not occupy space inside the tank


  • Very expensive.
  • High energy consumption

7. Coralife 77070 3X Turbo Twist UV Sterilizer

Coralife 77070 3X Turbo Twist UV Sterilizer
  • Fits: Up to 125 gallons
  • Power: 9 Watts
  • Flow rate: N/A

The Coralife 77070 is available in 3 sizes, which are the 3X (for up to 125-gallon aquariums), 6X (for up to 250-gallon aquariums) and the 12X, which is recommended for up to 500-gallon aquariums. This gives you plenty of options to consider for different tank sizes.

Regardless of the size, they are all external UV sterilizers, which means that they should be installed outside the tank. Each unit comes with mounting brackets for either hang-on or in-line installation.

Although it does not come with the piping required to bring water in and out of the unit, the mounting brackets make it very easy to set up. It can also be hooked up to an external canister filter’s return lines for an even easier installation process.

For compatibility, you can use this sterilizer for both freshwater and saltwater aquariums for it to treat the water using its 9-watt UV bulb.  


  • Available in 3 sizes
  • Comes with mounting brackets for easy installation
  • Can be installed independently or hooked up into the return lines of an external canister filter
  • Compatible for both freshwater and saltwater use
  • 9-watt UV bulb


  • Does not come with the required piping.
  • Water flow rate is not adjustable

How to Buy the Best UV Aquarium Sterilizers

How to Buy the Best UV Aquarium Sterilizer

1. Compatibility

Compatibility in UV sterilizers is mainly considered in terms of two things. First is the tank size and second is compatibility with salt or freshwater use.

For the tank size, it goes without saying that you should get a product that can comfortably work on the tank you have. If you have a 100-gallon tank, ensure that the UV sterilizer you buy is rated at least for an up to 100-gallon aquarium. 

For fresh or saltwater, most units can work on freshwater aquariums but not all are compatible with saltwater. The best thing to do would be to buy a product that is compatible with both so that you won’t have to worry in case you switch aquariums in the future.

2. Types of UV Aquarium Sterilizer

Submersible: Submersible UV aquarium sterilizers are more like self-contained units that can do everything on their own. They require no plumbing and have their own powerhead. The only thing they need is a connection to an external power outlet and that’s it.

However, they do occupy some space inside the tank, which might eat up into the scarce fish space available inside. For this reason, most of them are usually small in size and thus, meant for smaller tanks.

In-Line: In-line UV sterilizers are installed outside the tank, either independently with their own plumbing, or in connection with the return line of an external canister filter.

The good thing with this type is that it does consume any space inside the tank and thus, can have a large design for accommodating more features for better sterilization.

However, this unit’s installation process is a bit complex because it requires some plumbing and mounting.   

3. Power

The power of a UV bulb is a critical factor to consider before buying any sterilizer. Basically, the higher the power rating, the more powerful the light is and the more effective it is at killing microorganisms at the DNA level.

However, a high power UV bulb also consumes a lot of electricity and thus, for effective use, a high powered light should be complemented by a fast flow rate so as to purify more water per time.

On the other hand, low powered UV lights should be accompanied by a slower flow rate so that the light can penetrate the water and kill a big number of bacteria more effectively.

4. Flow Rate

The flow rate should be determined by the size of your tank. The bigger the aquarium, the faster the flow rate that you will need so that the sterilizer can turn over the whole volume of water in the shortest time possible.

For instance, if you have a 200-gallon tank, a 50 GPH flow rate is not appropriate for it. A value of about 200 – 300 GPH is the most appropriate to cater to its volume.

5. Ease of Installation

UV sterilizers are either installed using suction cups, which is the easiest method, or mounting brackets, which is just a little bit complex.

Suction cups are mostly used for submersible units while mounting brackets are used for setting up in-line sterilizers.


1. Do I really need the UV aquarium sterilizer?

A UV aquarium sterilizer is a very important gadget for your aquarium. Bacteria and other microorganisms are very likely to appear in every fish tank after some time. Regular filters can only handle so much but with these tiny organisms, even a 3-stage filter can be powerless.

The reason why removing these microorganisms is important is because they suffocate the fish. Well, they don’t strangle the fish, but they consume all the oxygen in the water, leaving the fish in an uninhabitable environment.

Again, murky waters don’t look very good on any aquarium. They prevent you from having good views of the fish and other decorations from the outside.

2. How does the UV aquarium sterilizer work?

The working concept of UV sterilizers is actually very simple. A UV light bulb inside the unit produces UV light at a certain wavelength (usually 250nm to 270nm).

Water is directed to flow around this bulb and as the light hits the microorganisms, it mutates and breaks their DNA structure, effectively killing them or liming their growth. The lack of these bacteria in the water makes it clean and clear. 

3. How long should I run the UV aquarium sterilizer?

This depends on a couple of factors, which include the size of the tank, the power of the sterilizer and the extent to which the water is contaminated.

For extremely green water in a big tank, you will need to run the sterilizer for a longer time as compared to mild contamination on a smaller tank.

While there is no definite answer to this, the most important thing is to run the unit until all the water is crystal clear.

4. Do I need accessories to install the UV aquarium sterilizer? What are they?

Most submersible sterilizers feature suction cups for instant installation. However, external, in-line sterilizers require mounting brackets for either hang-on or in-line installation.

5. How do I clean the UV aquarium sterilizer?

This is quite easy. Most of these sterilizers need to be cleaned on every bulb change. The steps below should be followed.

  • Disassemble the unit.
  • Remove the UV bulb.
  • Remove the foam filter and clean it thoroughly.
  • Clean the inside of the sterilizer
  • Attach a new UV bulb.
  • Reassemble the kit.  


After going through this article, you should have a better understanding of what a UV sterilizer and how it works.

You should also be able to differentiate between the different models from looking at their different defining features and determine the best UV aquarium sterilizer for your tank.

An important thing to note, however, is that UV sterilizers require your attention in order to function effectively. Ensure that the bulb is changed regularly and the unit is kept clean.