UV Pond Filters – What do they do?

Do you have a pond that has the appearance of a pea soup or something very similar? It is probably because you have an algae problem that you need to deal with. Even if you have a high-quality pump and filter in place, you are still likely to suffer from algae-related troubles, primarily because you are missing one very important piece of kit – a UV pond filter.

What is a UV Pond Filter?

A UV pond filter is a piece of kit that helps to clean up your pond by exposing the water to UV light that helps in the battle against algae that forms. On the following page, you will find out all you need to know about them including – how they actually work and where to install them among many other things.

How Do They Actually Work?

Basically, water is pumped out of your pond and into your UV filter, exposing single-cell algae present in the water to is exposed to extremely high levels of UV or ultraviolet light. The algae DNA is destroyed once it is exposed and this causes it to divide and die and then to clump together. Once the dead algae have clumped together it is easier to remove from the pond, returning it to its crystal clear appearance.

Important Point About UV Pond Filters

Although you may see a product description or title these accessories being referred to as ‘filters’, it is crucial that you understand that they are not actually filters. What a lot of people call UV filters are more accurately sterilizers or clarifiers because they do not actually remove the dead clumps on their own. The reason we want to make sure you understand this is so that you don’t buy a UV filter believing it will also remove the algae after it has killed it. You need to invest in a filter too.

Where Should You Place The UV Light?

Before you get ready to just shove your brand spanking new UV pond light sterilizer (not filter) into the water you need to understand that there are specific places you should set them up.

For most people who know a thing or two about pond accessories, the best place to install a UV pond light would be in line with the filter and pump. As the pump draws in water from the pump it passes it through the UV sterilizer light and then the filter removes the dead particles of algae.

However, you may wonder if it is better to place the light after or before the filter. Although it may seem counterproductive, it is actually better to place the UV light after the filter. The reason being is that the majority of UV lights work more efficiently and effectively when the water passing through or over it is clearer.

If there has already been a lot of debris and particles removed from the water in the filter, the light is then able to more deeply penetrate into the water and destroy more algae.

Another good reason for placing it after the filter is that any small rocks that happen to be sucked up from the pump could cause damage to the quartz sleeve that sits around the UV bulb in most sterilizers if it is placed immediately after the pump. In systems where the filter is placed first, this will help remove any of these potential risks to the bulb and its casing.

A further benefit of placing the light after the filter is that the filter can then trap sludge before it reaches the light, avoiding the buildup of sludge over the bulb and its casing. Although this creates a greater amount of sludge in the filter, as you need to clean this fairly regularly anyway, it is better that it builds up there than over your light.

Another Important Point About UV Clarifier Placement

You need to be careful to ensure that you place the pump feeding the UV light as far away as possible from the tubing that sends the water back into your pond.

If it is placed too near to the return tubing or additional outlets you may be using for aerators, fountains or even waterfalls, you are just going to be pumping water that is more or less clean. This reduces just how effective your entire inline pond filtration system actually is.

Cleaning UV Pond Light Sterilizers

As well as cleaning the actual pump and filters you have in your setup, you also have to regularly clean the UV lamp in your water sterilizer. Even if you have done as we have outlined above and placed the light after the filter, there will still be a build up of some sort of calcium and dirt on and around the quartz sleeve.

This calcium and dirt build up decreases how effective your UV light is and therefore you need to clean it once a year, at the very least. Be cautious though when cleaning the quartz sleeve as it can become more and more brittle with time and you could damage it easily if you are not careful.

What Is The Actual Purpose Of The Quartz Sleeve?

At this point, or if you have already browsed at some of the great UV pond light sterilizers available, that there is a lot of talk about the quartz sleeve. You may be wondering if this actually has a purpose or is just there to make the equipment look pretty. It actually does have a purpose.

As well as ensuring that no water makes contact with the electrical components of the UV lamp, it also protects the bulb and enables it to function properly and most effectively at the best temperature (which is 40 degrees Celsius or 104 degrees Fahrenheit.

We hope this not too exhaustive and long-winded guide to UV clarifiers/sterilizers is helpful to you. They are an important part of any pond setup but remember that you need to combine the functionality of a good UV pond light with a high-quality pond pump and filter too.