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Do I need a uv light for the pond?

A UV lamp keeps your pond clear. The UV lamp for the pond for example, it is extremely effective at removing floating algae. During the winter months, you don’t need to keep the UV light on, as there’s no algae growth at that time. But how exactly does a UV light work in a pond, and what should you pay attention to? In this article, we explain everything you need to know!

What does a uv lamp do for the pond?

A UV lamp is a special lamp through which the water is pumped. The pond pump directs the water toward the pond filter, where the UV lamp is installed. As the water flows past this lamp, the UV light kills floating algae, harmful bacteria, viruses, and fungi. The UV radiation destroys the DNA of these microorganisms. Disinfection with a UV lamp is therefore a perfect addition to your filtration system and prevents many common pond problems. It has no negative side effects on the pond.

Connecting a UV-C lamp to the pond

A UV lamp is always connected to the filtration system. If you want to use a UV lamp to filter your pond, you need to purchase a UV-C pond filter. These filters have a built-in UV lamp that helps purify the water.

Catalogue 2025

Download the new Filtreau catalogue today! UV-C lighting, as well as filters and accessories.

When should you turn on a UV lamp?

When the water temperature rises above 10 °C, you can turn the UV lamp back on. The fish become active again, and the pond season begins, usually around March. At this time, floating algae also start to grow again. You can prevent this growth with proper filtration and UV-C treatment. UVC filter. Also make sure to start up the pond properly with extra pond bacteria. 

When should you turn off a UV lamp?

It is always important to test the water quality of your pond regularly. This helps you determine the best moment to turn off the UV lamp. As a general rule, the lamp can be turned off when the temperature drops below 10 °C, since hardly any harmful algae grow in the pond at that point. In most cases, this is between November and February. Turning off the filter lamp reduces your energy costs, which is of course good for your wallet.

How often should you replace the UV lamp?

In general, a UV lamp is replaced every pond season. Over time, a UV lamp loses its filtering power and becomes less effective at destroying the DNA of bacteria, fungi, and algae. The lifespan of Filtreau UV lamps ranges between 8,000 and 13,000 operating hours, which equals roughly 12 to 15 months. Depending on how long you keep the lamp on, you will need to replace it accordingly. Most people choose to replace the lamp once a year to ensure it continues to provide the most efficient filtration.

The actual lifespan of a UVC lamp is determined, among other factors, by the cooling of the lamp. During its lifespan, the intensity of a UVC lamp gradually decreases.