When the water in your Koi pond gets green, you know that is the time to get a new UV sterilizer. The exceeded food causes the growth of algae, bacteria, parasites, viruses and other microorganisms, making the water less clear and full of bad odors. A UV light can clean the water up, keeping a healthy environment for you Koi fishes.
Here are the best uv lights for koi pond you can buy in 2023:
- Best Overall: Jebao CW-55
- Easy to install: Coralife Turbo-Twist UV Sterilizers
- Best For Smaller Ponds: Flexzion CUV-118
- Best For Big-Sized Ponds: OXYFUL 36W Non-Submersible UV Ultraviolet 21.5” Light
- Best For Green Algae Control: Pondmaster DNR02920
|5 Best UV Lights For Koi Pond|
Easy to install
|Coralife Turbo-Twist UV Sterilizers|
Best For Smaller Ponds
Best For Big-Sized Ponds
|OXYFUL 36W Non-Submersible UV Ultraviolet 21.5” Light|
Best For Green Algae Control
Best Overall: Jebao CW-55
- Versatile – compatibility with many fitting tubes and pump sizes
- Flexible – available in horizontal and vertical setup
- Easy to install - the 22' ultra-long power cord
Though there's no UV light for every Koi pond, we confidently assure you the Jebao CW-55 is the most versatile option in the market that can work well on most ponds.
At 55W, it effectively cleans and removes odors from 8,000 to 10,000 gallons.
You can have the light connected to any available fitting tube and pump size whether it's 1-1/2", 1-1/4", 1", or 3/4". You also can install it either horizontally or vertically. As an added plus, the setup is easier thanks to the 22' ultra-long power cord.
|Jebao CW-55 Specifications|
28 x 9 x 8 inches
compatibility with many fitting tubes and pump sizes
available in horizontal and vertical setup
the 22' ultra-long power cord
The Jebao CW-55 has all the qualities of the best overall UV light for Koi pond at a very affordable price.
Easy to install: Coralife Turbo-Twist UV Sterilizers
- Effectively removes algae, parasites, and bacteria
- Twist-flow design & Indicator light
- Can be hung on or in-line installed
- Works with both freshwater & saltwater
- Low suction power
Coralife Turbo-Twist is ideal for Koi newbies. You won’t want an over-complicated UV Sterilizer; Instead, you’ll want an easy to install, easy to use, and easy to maintain UV Sterilizer, which Coralife Turbo-Twist meets all.
Coralife Turbo-Twist has a twist-flow design which helps increase the exposure of water to UV light, maximizing the clean effectiveness. It features an indicator light, which helps you know whether the sterilizer is on. You can easily hang Coralife Turbo-Twist or in-line install the sterilizer. And it works with both freshwater and saltwater.
The main drawback of Coralife Turbo-Twist is the suction power, which may be considered low. It is recommended for up to 250 gallons of water.
|Coralife Turbo-Twist UV Sterilizers Specifications|
16 x 9.2 x 3.2 inches
Twist-flow design & Indicator light; up to 250 gallons
Coralife Turbo-Twist is an easy to install & use UV sterilizer for small tank.
Best For Smaller Ponds: Flexzion CUV-118
- Compact – the measurement of 17 x 13 x 7 inches
- Ideal for ponds under 2000 gallons in size – 18W power
- High-quality & safe - leak-proof rubber seals and low-energy consuming safety mechanisms
- Vague instructions
For small Koi ponds, the Flexzion CUV-118 is the best performer.
Its compactness is the very first highlight. Measured by 17 x 13 x 7 inches, the UV light can be easily set up and fit most limited spaces.
Next is the 18W power, which is both powerful enough for ponds under 2000 gallons in size and is energy-saving.
Although the unit is lightweight, small, and inexpensive, its durability and quality is no joke. The outer ballast with power switch, leak-proof rubber seals, and low-energy consuming safety mechanisms are some typical examples.
|Flexzion CUV-118 Specifications|
17 x 13 x 7 inches
the measurement of 17 x 13 x 7 inches
If you are looking for the best UV light for small-sized Koi pond, look no further than the Flexzion CUV-118
Best For Big-Sized Ponds: OXYFUL 36W Non-Submersible UV Ultraviolet 21.5” Light
- Very powerful – able to clean up to 14,529 gallons
- Energy-efficient - 36W power
- Sturdy - water-resistant housing
- Short power cord
- The unit gets warm a little bit while operating
Opposite to the Flexzion CUV-118, this UV light from OXYFUL is specifically engineered for large-sized Koi ponds up to 14,529 gallons based on its 1,849 GPH performance.
But what truly makes it superior to other similar counterparts is the energy efficiency, at only 36W. So, you're reassured to have this light turned on continuously with no fears of the increasing energy bills.
A big plus for the highly water-resistant housing.
|OXYFUL 36W Non-Submersible UV Ultraviolet 21.5” Light Specifications|
25.1 x 8.3 x 5.9 inches
able to clean up to 14,529 gallons
Powerful yet energy-efficient, the OXYFUL 36W Non-Submersible UV Ultraviolet 21.5
Best For Green Algae Control: Pondmaster DNR02920
- More efficient results in killing green algae - the thin diameter & the vortex flow design
- Flexible – able to be installed outside the pond or fully submerged in the pond
- Cool looking & Less destructive – black color
- Big and bulky
For medium-sized Koi ponds with serious green algae problems, the Pondmaster DNR02920 is a more-than-better solution.
While the way it works is quite similar to other counterparts: Pump the pond water through the light and use UV rays to kill suspended algae, there are two improved features making it ultra-efficient.
Firstly, the vortex flow design helps increase the time that the water is exposed to the UV light. Secondly, the thin diameter helps the water get closer to the UV rays.
We also like the fully submersible design and the unobtrusive black color.
|Pondmaster DNR02920 Specifications|
18.5 x 6 x 6 inches
the thin diameter
the vortex flow design
fully submersible construction
The Pondmaster DNR02920 controls a medium-sized Koi pond with serious green algae problems.
How To Choose The Best UV Light For Koi Pond?
Choosing a UV light is pretty simple. You’ll want to know two important specs: the pump’s capacity and the UV light wattages. The pump should support the capacity of your pond. Every UV light has a recommendation on the pond size in its description, you'll need to read this through. You can evaluate your pond size by this simple calculation: Length (ft) x Width (ft) x Depth (ft) x 7.5 = Gallons.
The wattage of the UV light determines how much water it can clean (per hour). For a small pond, you'll just about 10 - 20 W. For a medium pond, you'll need less than 50W. For a larger pond, you may need higher wattage.
Other things you also might want to put into consideration are the size of the UV light, its weight, or its safety features.
Which Brands Make The Best UV Light For Koi Pond?
Jebao is a Chinese manufacturer of fish tank equipment, headquartered in Zhongshan. It was founded in 1998; up to present, it has built its worldwide reputation on fountain pumps, lights, aquarium accessories, and UV sterilizers. Their products are famous for high energy efficiency, which means they will save you a lot of the electricity bills and help protect the environment. Jebao also focuses on quality control and safety features, they have met a bunch of international certifications, such as GS, UL, CUL, BS, SAA.
Not only in China but Jebao is also now famous across the world, the US, Canada, Germany, Singapore, and the UK is its main export markets. Jebao is the brand you can trust.
Coralife is a sub-brand of Central Garden & Pet, an American traditional company in the garden & pet industry. It was founded in 1980 and has built its brand on a wide range of garden and pet products. They have a strong retail network across the globe, ensuring great customer services for each customer. They are famous for innovation and high-quality products with about $2 billion in annual sales.
When it comes to fish pond products, Coralife has LEDs, Light fixtures, Protein Skimmers, UV sterilizers, Chillers, Filtrations, Power managements, Digital thermometers, and other accessories. If you are finding some tools for your fish pond, Coralife is a to-go brand.
As you can see from the name, Tetra-fish focuses on products for fishes and ponds. They have a very long history, since 1951, and now is the biggest manufacturer of aquarium fish food. Besides, they provide a very wide range of products for fishes and ponds.
Their products are among the best you can find in the market, both quality, appearance, and features. Coming with a very high-quality product is a higher price. Tetra-fish's UV sterilizers cost a little more than other products; however, it is really worth it.
Why do I need a UV sterilizer?
When the water in your koi pond gets green, you know that is the time to get a new UV sterilizer. The water in a fish pond may get polluted by algae, bacteria, parasites, viruses and other microorganisms, making the fishes die and causing unpleasant smells. A UV sterilizer can clean them up, keeping the water crystal clear, both freshwater & saltwater.
How does UV sterilization work?
Each UV sterilizer has a built-in UV light. This light destroys chemical bonds and messes up the DNA/protein structure, making microorganisms death. These microorganisms include bacteria, parasites, viruses, and even algae. When the water is pumped into the barrel, the UV light will get their work done, keeping the water clean.
How long does it take for UV to clear green water?
From my experience, if you install a new UV light for an old green-water pond, it may take five days to clean the water up. The water then will be crystal clear. However, it depends much on the capacity and power of the UV light. Some will take longer and some will take less time.
How to improve bacteria and algae control?
The main reason that causes algae and bacteria growth is the exceeded food and nutrients. To improve bacteria and algae control, you can use bioaugmentation containing beneficial bacteria & enzymes. These bacteria and enzymes help resolve the exceed food; moreover, it maintains the water’s PH, keeping the water clean and healthy for koi fishes.
Where do you put UV light in a pond?
UV lights are often for external use, which means you cannot submerge into the water. You can in-line install it after the filter. So, the water after being filtered to get rid of bigger bits of dirt will be filled in the UV light's barrel to remove microorganisms, such as bacteria, parasites, viruses, and even algae. Some UV lights include a filter; for these UV lights, you just need to place it directly to the pond.
A good UV light can keep your pond clean, clear, and healthy for Koi fishes. Hope that my review helps you to choose the best UV light for your Koi pond.