What is an ultraviolet pond filter? It’s a machine that works to clarify pond water by killing the algae that lives in the pond. An ultraviolet filter is a supplement to a traditional physical pond filter. It is also called an ultraviolet clarifier or a UVC, since it does not actually physically remove algae from the pond. UVC systems are often used to stop the suspended algae that cause green water.
The Cost of UV Clarifiers
An ultraviolet clarifier is not cheap, but like any pond feature like a distinctive waterfall or fountain, it can provide the serious pond owner with the desired pond environment. UVC systems run from $200 to $600, and extra bulbs cost between $40 and $60.
Controlling Pond Algae
There are several approaches to algae control in the pond. The first is to create a pond environment that is unfriendly to algae. In a koi pond, this means controlling the amount of fish and fish food present in the pond. It also means ensuring that there is adequate shade over the pond so that the pond remains cool and oxygen-rich. Finally, reducing algae levels involves oxygenating the pond with devices like bubblers, waterfalls, or fountains.
The second approach to algae control is to manually remove algae from the pond. This might involve hand-picking mats of algae from the pond or using a filter to remove algae. A basket-style filter will move water into the filter from the pond and capture the algae that is present.
UVC Systems Can Assist With Water Clarity Problems
For those who have a severe algae problem or who require greater clarity in the water, an ultraviolet filter will not capture the algae, but it will actually kill the algae cells. Just like ultraviolet light can damage skin cells, the light from the low-level ultraviolet emitted by a UV pond filter damages the cells of algae. This filter is a supplement to the other filtration solutions and not a solution in itself. However, a UV filter can work well with a physical pond filter.
Questions to Ask About UV Pond Filters
Ultraviolet pond filters come with different features. Here are some key questions to ask before buying a clarifier:
- What size of pond will this clean?
- Is this product submersible? UV clarifiers are often not submersible, and the body of the clarifier must be located outside the pond.
- How long is the anticipated lamp life?
- How much are replacement bulbs, and can they be purchased at the same store?
- Is there a warranty, and how long is the warranty?
- If there is another water feature in the pond, make sure that it is safe to use both pieces of equipment at the same time. Sometimes water features can damage clarifiers.
While a UV clarifier is not the algae control solution for everyone, it can be a good way for some pond owners to reduce green water and kill pond algae. Combine a UV clarifier with other pond algae control solutions to achieve the best algae control.
Tricia Edgar - Tricia Edgar is a gardener, environmental educator, and science writer from the Pacific Northwest.
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