The UV Sterilizer is one of the most praised and most critiqued piece of equipment in both freshwater and saltwater aquariums. It’s easy to see what because the quality of the sterilizer differs greatly and many people do not know the difference. It’s easy to just purchase a cheap UV sterilizer and expect it to work wonders for disease and algae management. I was a little hesitant to write this article at first , but there is a lot of misinformation out there with these products so I feel it’s best to write a comprehensive article educating people on how they work so you have reasonable expectations of what you will get out of them.
The best UV sterilizers are expensive, but have the ability to to mitigate pathogens in the aquarium. The cheap UV sterilizers will often only be best for water clarification. With that being said, let’s talk about what exactly is a UV Sterilizer.
In A Hurry? The best uv sterilizer is the TMC Vecton!
What is a UV Sterilizer For A Fish Tank?
A UV sterilizer is a filtration unit that uses a germicidal florescent lamp that uses a particular wavelength (254 nm). Water is delivered to the unit via a pump where the water passes through a quartz chamber. As the water passes through this chamber, the UV light damages algae, parasites, and bacteria’s DNA preventing them from growing and reproducing.
UV sterilizers have been a topic of discussion regarding the fight on superbugs. Superbugs are evolved (or mutated depending on how you want to label them) pathogens which are drug resistant. UV light has showed to attack parasite resistance as it destroys the DNA. If you own a marine aquarium, you may be familiar with drug resistant ich and marine velvet coming through aquarium trade supply chain. This is a must watch below:
UV Sterilizer Dwell Time And Why It’s So Important
The time spent in the quartz chamber is known as dwell time. This dwell time is something you are going to write down as you research UV units as this is the most important factor when deciding what the best UV sterilizer is for your budget.
UV Sterilizer in theory, are all designed the same way with a sleeve and UV bulb, but certain units have larger dwell time due to the width and length of the quartz chamber. The longer and wider the chamber, the higher the dwell time. You can also increase the dwell time by lowering the flow to the unit, but if the unit is too short and not wide enough you will hit a limit to the sterilization you can achieve. The longer dwell time you have, the longer the water is exposed to the UV sterilizer light. This in turn means there is a higher likeihood that all pathogens/organisms passing through the UV light will be affected. So how do we rate dwell time? The best way to rate this is to categorize the level of sterilization and what this means when choosing a filter.
UV Sterilizer Levels – Not All Are Created Equal
Knowing the sterilization levels a unit can achieve is what you need to know as a consumer in order to purchase the best uv sterilizer for your fish tank or pond. We can break down UV sterilization into 3 uses.
- Green Water Clarification (Clarification)
- Bacterial, Flagellates, and Light Parasite Sterilization (Sterilization)
- Heavy Parasite Sterilization (Heavy Sterilization)
The best sterilizers on the market can do the 3rd category. The middle grade models can do the 1st and second. Budget units can only do the first.
UV Clarification – The Most Common Sterilizer on the Market
The first category of UV Sterilization is the main reason why UVs can such a bad rap in the industry. The vast majority of UV sterilizers available for sale will only be capable of clarification. In freshwater tanks and ponds, this is still a very good unit as it will eliminate green water, but don’t expect it to do anything for bacterial and parasite mitigation or redox balance. This sterilizers are usually hang-on or internal which makes them easy to install. These UV sterilizers offer little dwell time and comprise of many cheaper sterilizers on the market.
Sterilization – Mid-Level Units
We start getting into more serious UV sterilizers at level 1 sterilization . These units are capable of actual sterilization with their higher dwell time. These units are most suited for common fish tank and pond usage. They have enough dwell time to not only clarify water, but can destroy harmful viruses and bacteria in your aquarium. Level 1 sterilizers are particularly useful in marine aquariums at helping to eliminating dinoflagellates.
Heavy Sterilization – The Best of the Best
This category represents the uv sterilizers with the best dwell time. They are the best of the best in the industry and common of what you will see in public aquariums. That is not to say that this is not available to the common hobbyist, it’s just that sterilizers of this level are very expensive in comparison to others that do not have the dwell to be in this category. These units are fully capable of water clarification, disease mitigation, redox balance, algae containment, and suitable for increasing the disease resistance of your fish population.
What Is Redox And How It Relates to UV Sterilization
I mentioned redox in the discussion about sterilization categories, but did not define it. Redox refers to ORP (Oxidation Reduction Potential). This relates to the degree of water purity in your aquarium. An effective UV sterilizer will increase your redox potential. If you want the full explanation. You can view the full explanation from Reef Sanctuary.
The Best UV Sterilizers for the Money
Now that I have explained how sterilizers work and what the levels of sterilization are, let’s discuss the best UV Sterilizers for fish tank and ponds.
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Below is the comprehensive list of units with their category of sterilization listed.
1. TMC Vecton – The Best UV Sterilizer On The Market
The TMC Vecton is without a doubt the best UV sterilizer on the market. At first, you may think what is this brand and what makes the unit so great. TMC stands for Tropic Marine Centre, which is based out in the United Kingdom. TMC has been leading the UK in fish trade since the 1970s and specializes in high end aquarium equipment with reef tanks being their main focus. The are the leading supplier in the UK for livestock and design their own equipment, with their equipment being used in commercial facilities all over Europe. You can learn more about them in the video below. I wish we had more suppliers like this in the US:
So now that you know who TMC is let’s talk about why this unit is the best available.The main thing that makes TMC Vectons so great is their dwell time. They have the longest dwell time available in a sterilizer because their chamber is very wide. The UV bulb is also unique from other makers in that they use a wider T8 UV bulb versus a the standard T5 used in most UV sterilizers. This wide UV bulb is more effective at sterilizing than other units in the market.
The next thing to love is how the unit is assembled. It comes with its own docking bay so you can easily mount to your aquarium stand or wall. This docking bay allows you to pop up the bay and perform maintenance on the unit and keeps the electronics safe and secure. The sterilizer also comes with a swivel arm that can be placed at the top or below of the unit for ease of install and adapt to piping.
The main downfall with this sterilizer is its availability. Because it’s made in the UK, it’s difficult to find their small units available unless you purchase a transformer. The 25 watt unit is the main UV sterilizer you want to look for and will handle small and large tanks. The UV light and its dwell will outperform larger wattage units. This UV light will be the equivalent of 40 watts for many other UVs out there. The UV bulbs will also need to be special ordered, but given the performance this unit provides and the fact that it is a bargain over the more expensive Aqua UV classic makes these worth it.
- The best heavy sterilization available to the hobbyist
- T8 over T5 provides the highest dwell time available
- Docking bay is an excellent feature that makes this unit easier to install
- Hard to find and order
- Only 25 watts
2. Aqua UV Advantage – Hang On The Back Sterilizer for Small Tanks
The Aqua UV Advantage series is a hang on the back UV sterilizer specifically made for small and sumpless tanks. Aqua UV makes some of the best UV sterilizers in the market and they haven’t skipped on their well known quality in this unit. This UV sterilizer has the same quality build and larger dwell chamber. It is a bit small to qualify as a sterilizer capable of level 2 sterilization, but it is a strong first category sterilizer and there are honestly very few high end sterilizers available at this size. If you have a sumpless fish tank, this is a great UV sterilizer to look into.
- Compact size
- Works with sumpless tanks
- Quality sterilization
- Smaller dwell time than the classic models
Best For: A sumpless fish tank
3. Green Killing Machine – Simple To Use Green Water Clarifier
For those of you looking for an easy to use sterilizer out of the box, the Green Killing Machine is a great unit to get. It works internally with a pump included. The Green Killing Machine is small enough to fit in a small sump or inside your fish tank where you plants or rock can hide it. This unit is not very powerful though. You will need to purchase this knowing it is only a UV capable of clarification, but it does a great job of clearing up green water out of the aquarium. Just see the differences below of what this little UV light can do.
After 6 days:
If you have a green water problem, the Green Killing Machine is perfect for you. It is cheap and easy to use. The Green Killing Machine is very effective at what it is marketed for, which is removing green water.
- Cheap ready to run unit
- Can be run internally in the display tank
- Only capable of clarification
- May be too large to work in all in one aquarium chambers
Best For: A fish tank having green water problems
4. Aqua UV Classic – Best UV Sterilizer Made in The USA
The Aqua UV Classic is the gold standard in UV Sterilizers in the market, especially in the US. This is an American Made UV Sterilizer that has a great dwell time capable of heavy sterilization. One of the models can be very large like the 40 watt model that is a 44 inch unit! The length of these units is to increase the dwell time of the UV light as much as possible. This units are meant to be run in an aquarium sump or separate area for pond usage. If you are looking for a top quality American Made UV-C light, look no further than Aqua UV. They are expensive, but worth the investment for what they can do. Just get the non wiper variants if you are purchasing this UV Sterilizer for a saltwater aquarium.
- American Made UV sterilizer
- Capable of heavy sterilization
- Many sizes so they can handle very large aquariums and ponds
- Large – they are best in sump and basement/fishroom setups
Best For: A large fish tank with sumps or canister filters. Ideal for ponds
5. Bloom Clean UV Sterilizer – Cheap UV Clarifier For Small Tanks
The Bloom Clean UV Sterilizer is one of the cheapest sterilizers on the market. They are perfect for those with small tanks and just want something that gets rid of green water. It has no fancy sleeve or chamber like others. Make sure to keep the uv light in a hidden area. It is very bare bones, which is why they are so cheap. You will want to use them in an all in one aquarium chamber or in a larger power filter away from the main display tank. As a clarifier and the price, it is great for a budget fish tank keeper and a cheap solution for those who want to get rid of green water.
- Compact and will fit in power filters and all in one chambers
- Only a clarifier
- Bare bones – no sleeve to block UV light to rest of tank
Best For: A small fish tank with power filters or all in one aquariums
6. Coralife UV Sterilizer – Mainstream UV Sterilizer
The Coralife Turbo Twist UV Sterilizer is probably going to be the most widely available UV sterilizer on this list. The main feature with this UV Sterilizer is that it has a twist chamber which really cuts down on the size making this a compact unit even for it’s larger models. It still needs to be used with a Canister Filter or a Sump, but you can work with smaller spaces with it. Given it’s twist chamber, it has the added dwell time that makes it a first category sterilizer, which will satisfy most requirements for fish tank and pond keepers. Overall, it’s a good all around unit that is easy to find in stores and easy to get UV bulbs and replacement parts.
- Widely available UV Sterilizer
- Compact Size for its dwell time
- Can be used in an all in one tank
- Pricey for a first category sterilizer
Best For: Aquariums with sumps or canister filters
7. Innovative Marine Auqa Shield UV – UV of Choice for All In One Aquariums
Finding a quality UV sterilizer can be frustrating for those with all in on tanks because of the size of the chambers. Innovative Marine has addressed this issue with their very own AUQA Shield UV Sterilizer. This high quality unit is made to work in your first chamber with a sponge prefilter so you can still have space your other equipment like media reactors and protein skimmers or additional biological media.
Innovative marine makes this a very easy to use unit as the uv sterilizer bulbs work in cartridges that you just pull out and dispose off when they are ready to be replaced. this makes maintenance and install very easy and one of the easiest and carefree units to operate on the list. Innovative also makes a universal model that hang right into a aquarium sump for those of you with small sumps that want a plug and play unit. These units are capable of the first category of sterilization so you will be getting a standard sterilization, which should suit most aquarists needs.
- Compact and works in all in one aquariums
- Disposable cartridges make this easy to maintain
- Comes with a prefilter
- Larger models not available for big tanks
- A bit on the pricey side
- Low wattage
Best For: All in one aquariums
8. Lifegard Prostep UV Sterilizers – A Good UV Choice for Canister Filters
The Lifegard Prostep UV Sterilizer is a inline sterilizer that is made to either hang on your tank or stand inside your stand. Given the way they are built and how they work, they are best for canister filter setups as they can sit right next to your canister filter in your stand. This is an easier and trouble free setup than say your Aqua UV classic, which does not come with any mounting equipment and you have to worry about fitting a giant UV sterilizer in your stand and buying mounts for it.
This unit has pushes water through the UV sterilizer in a step pattern to maximize the dwell time in the chamber. This puts this unit at the higher end of the first category sterilizers but at a much cheaper price than the Aqua UV classic. While it is not at the performance level of a UV Classic, it is close enough where if one is considering a higher end UV this will be seen as a bargain unit. You can also hang this on the back of your fish tank or sump, which give this extra versatility
- Works great under the cabinet with its standalone design
- Step design gives good dwell time
- More advanced install then cheaper units
- Hang on is still pretty large for even at the 15 watt models
Best For: Canister filter powered aquariums
9. Jabeo UV Sterilizer – The UV of Choice for Dinoflagellates
The Jabeo UV Sterilizer in my experience usually comes into play when I have someone I know dealing with a dinoflagellates outbreak. You need at least a level 1 sterilizer to kill dinos and the Jabeo is a cheap and effective unit to use to handle them. They are big units with a good amount of dwell time. For the price and size, they are good units to consider and also work very well in ponds clearing up green water and providing clarity in the water.
What I don’t like with this unit is the ballast is bulky and will not detach from the sleeve assembly. This makes it a bit of a pain fitting it into a cabinet because you have to provide a hole big enough to fit the ballast in. The UV sterilizer bulbs are easy to find online and you know that it is a solid first category sterilizer. It is a good all around unit and one of the better Jabeo units on the market next to their DCP aquarium return pumps and SOW wavemakers.
- Cheap for the performance you get
- Inlet and out adjust up and down for easy adjustments
- Readily available UV bulbs
- Made to be made inside a cabinet
- Ballast is large and annoying to work with
Best For: Tanks dealing with dino outbreaks and larger tank owners who want some parasite control
The Best UV Sterilizer (Our Recommendation)
Like I usually do, I’m going to provide a list as it will depend on your aquarium and needs. Here is what I would recommend.
Best UV Sterilizer for Nano and All In One Tanks – Innovative Marine AUQA
Best UV for Clarification – Green Killing Machine
Best Value – Aqua UV Advantage
Best UV Overall Sterilizer – TMC Vecton
UV Sterilizer FAQs
UV sterilizers fall in the more advanced category of fish keeping equipment so these FAQs should hopefully help out.
How Do I Install A UV Sterilizer?
It will depend on the make and model you purchase, but I’m going to supply the video of one of the best out there from TMC to show you know the installs work. Many of these units are designed to be ready to run with some tubing required on your end to purchase or a pump or outlet source to be provided.
How Often Do I Change UV Bulbs?
You should change your UV bulb every 6-12 months. You can stretch it to 12 months if you want, but the effectiveness of the UV bulb decreases as it ages so you do not want to go too long not replacing them. If you replace your UV bulb every 6 months, you can ensure that you have the optimum performance running 24-7.
Can UV Sterilizers Really Eliminate Ich?
Freshwater (Ichthyophthirius) and Saltwater (Cryptocaryon) ich is always a big topic in disease when it comes to our hobby. Some people will tell you that a UV sterilizer can eliminate ich, but that is not the case. A UV sterilizer will not completely eliminate ich, but it will be a very useful tool in disease management, particularly hobbyist who are not willing to quarantine fish. If you are buying the healthiest stock you can get, there is still a decent chance (much higher chance with marine fish) that there will be ich present living in your fish tank. Sterilizers will eliminate the free floating ich stage in your aquarium, but it will only eliminate the free floating parasites that manage to make it into the sterilization chamber. You will have less parasites with a level 1 or level 2 sterilizer, which will increase fish immunity.
How Many Gallons Per Hour (Flow) Does My UV Sterilizer Need?
Here is a real simple chart to sort out what gallons per hour you need to run through your UV sterilizer in order to achieve the proper sterilization stages:
40-50 GPH per watt for most
50-60 GPH per watt for Aqua UV Classic/Vecton
20-30 GPH per watt for most
30-35 GPH per watt for Aqua UV Classic/Vecton
10-12 GPH per watt for Aqua UV Classic/Vecton
Conclusion (Best UV Sterilizer Reviews)
I hope this article helps dispel a number of myths about UV sterilizers. Judging performance on UV sterilizers is all about knowing dwell time and separating the various players in the market by how much dwell time they offer. Once you know that, you can chose the UV sterilizer based on your needs and budget. If you have any questions, please leave a comment below. Thanks for reading.