Tetra Pond Pond UV Clarifier

1. Tetra Pond GreenFree UV Clarifier

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If you’re going through online UV pond sterilizer reviews, you’ll likely notice that this Tetra Pond UV clarifier almost always steals the #1 spot. But is the hype justified?

Our vote is yes. We found that this pond UV sterilizer gave excellent results and also had a great price-to-performance ratio. It’s sturdy and durable, while being well-designed and versatile enough to work in almost any type of pond.

Depending on the size of your pond, you can usually find different versions of this pond UV clarifier ranging from 660 all the way up to 8800 gallons (with bulbs ranging from 5W up to 36W).

The system is simple – similarly to most UV units, water flows into the tube, and the algae becomes exposed to the UV light. This exposure prevents algae reproduction, which in turn kills it. Then, the UV clarifier releases the dead algae back into your pond, where they group together, creating little clusters. The dead algae is further flushed and filtered out of your pond naturally, leaving only clear water within a few days.

Even for beginners, we found that it’s easy to set up and use, plus it comes with a long power cord along with the sterilizer, which makes the cleaning process much easier.


Pond UV Clarifier

2. TotalPond UV Clarifier

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Our #2 pick is a relatively cheap UV sterilizer when compared to many competitors on the market. Unlike Tetra’s Pond GreenFree, this one doesn’t come in multiple wattages in sizes – instead, you’d need to use several if you own a huge pond.

One unit is suitable for ponds that hold up to 2000 gallons of water. The design, although simple, is pretty clever – and does an efficient job at cleaning algae.

The pond UV light runs on a 9-W bulb, which should be plenty for most types of pond algae. Installation is fairly simple and versatile – it can be used as as a submersible pond UV clarifier, but can also be positioned outside of the pond itself.

Finally, the indicator light is a handy feature – it allows the user to easily keep an eye on whether the clarifier is operating or not.

Before trying out this submersible pond UV clarifier, it’s advised to use it with TotalPond’s #DD11330 or #DD11560 pumps and pump outlets that have 1/2, 3/4 or 1-inch ID tubing.


PondMaster Pond UV Clarifier

3. PondMaster 20-W Clarifier/Sterilizer

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A solid choice at a fair price. In comparison to most products you’ll come across, this is a pretty affordable UV sterilizer.

Similar to our #2 pick, it can function as a submersible UV sterilizer, but you can also set it up outside your pond. Suitable for 3000 gallons, the pond UV light runs on 20W. We found that it’s extremely thorough, but also sturdy and durable.

However, the best part about this pond UV sterilizer is its design. It isn’t too bulky and is nicely hidden if you install it inside your pond. The recommended pump for it should be capable of pumping 1800 gallons of water per hour. Another cool feature is the sterilizer’s blue light – it turns on to let you know that it’s working properly.

In the packaging, you’ll also find an 18-foot power cord.


Jebao 55W UV Clarifier

4. Jebao 55-W UV Clarifier

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If you own a large pond, but don’t want to spend a fortune on a UV sterilizer, this is a solid choice.

Although many Chinese manufacturers get mixed reviews regarding their sterilizers, Jebao often offers good quality at a good price. This UV sterilizer is no different – at 55W, it’s an algae annihilator. If your pond is suffering from a heavy algae infestation and algaecides and 9 or 20-W bulbs just don’t seem to cut it – we’d recommend this pick. However, it isn’t submersible, which some might find problematic.

A 20-foot long weather resistant transformer is also included.


Submersible Pond UV Sterilizer

5. Jebao 36-W UV Pond Sterilizer

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Our last pond UV sterilizer is similar to our #4 – it’s from the same brand and operates in a very similar way. However, it’s a bit weaker in terms of power. This 36-W version also isn’t submersible and can be used to get rid of algae in aquariums and ponds.

Although it’s not our favorite pick, we found that it did a solid job at filtering out algae. However, the process lasted over 5 days. Just like our previous pick, this pond UV sterilizer comes with 3/4″, 1″, 1-1/4″ and 1-1/2″ fittings. A 22-foot cord is also included in the packaging. A very handy aspect is that there’s a little light that comes on when the device is working properly.

In order to get the best results, it’s recommended to install this UV clarifier to the tubing that is connected to your external pond filter.


How does a pond UV clarifier work?

A pond unit works identically to an aquarium UV sterilizer. The unit consists of a chamber which water is pumped into. The UV light is inside this water chamber. When water passes through it, the UV light kills the algae which is responsible for turning your pond water green. The water is pumped back into the pond and the dead algae start to clump together. These clumps fall to the bottom of your pond and are flushed out via natural filtration. In approximately 3-5 days, you should see a change in your pond’s water.

The bulb needs to be hidden and inaccessible to actual fish, shrimp, or any other living organisms – because UV light is highly dangerous to all living beings.

How to test if a UV bulb is working

Never look at exposed UV light, because it can cause damage to your eyesight. So when you perform a checkup, make sure never to stare directly at the UV light.

Disassemble the ultraviolet pond sterilizer so as to expose the bulb. Some sterilization units usually have a protective glass cap that goes over the the UV bulb. Look for a small black button/switch underneath the bulb. It’s usually located at the base of the UV light. Before pressing it, turn your head away. If the light comes on when you press the button, the unit is working. If it doesn’t come on, the bulb has either gone out or isn’t sitting properly. In that case, make sure that everything is in its place and that the bulb isn’t loose, because this might lead you to believe that your sterilizer isn’t working.

What’s the best UV light for a Koi pond?

If you own a Koi pond, we recommend getting a pond UV clarifier that has a slower water pumping flow, because if it’s too fast, this might upset and stress your fish out; Koi love slower currents. A water pump with a flow of 1800-2000 gallons per hour should be just right.

How many watts of power should my pond UV clarifier have?

The truth is – UV light can be harmful, and too many of it is never a good thing. UV bulbs also need replacing every now and then – and the costs of maintaining a pond can pile up quickly.

You should always choose a UV sterilizer depending on the actual amount of algae you’re struggling with. A sterilizer with a 9-W bulb will struggle with a huge outbreak of algae in a large pond, but it’s a much safer, saner, and more economical choice than a 55-W if you don’t have much algae or just want to take precautions.