How often do you need to change UV Bulbs?

How often should I change my UV bulb?

UV sterilisers have been used in modern times to sterilise water in aquariums and fish ponds. UV sterilizers are highly effective at clarifying green water to clear, tackling algae and also removing harmful bacterial pathogens from the water, preventing disease.

Typically, an Ultraviolet or UV lamp lasts 12 months or about 9000 hours of use. The light stays lit longer than 12 months but after one year of use it's ability to kill bacteria will slowly diminish, leaving your fish tank or pond fish vulnerable to disease. It ability to clear algae will also be reduced. So you should change your UV bulbs at least once a year.

uv bulb


How long should my UV Steriliser be left running for?

An aquarium or pond UV steriliser should be switched on and running for 24 hours a day, 365 days a year. Exceptions would include perhaps when cycling the fish tank before there are any fish in it, to allow the beneficial bacteria establish in the water (UV light kills bacteria) or if you are using a specific treatment or medication that stipulates that UV's should be turned off.

How can I tell if my UV sterilizer bulb is working?

Your UV Sterilizer unit will have a clear portion of plastic, a viewing window or porthole, or some type of indicator that allows you to see if the light is burning. You should never open a unit and look directly at a glowing UV lamp as it can cause eye damage. If the lamp is not glowing then lamp needs replacing. If it still fails to light up, then it could indicate a problem with the ballast or another electrical component.

How often should UV bulbs be cleaned?

A UV lamp should not be cleaned. Instead, it should be replaced at least every 12 months or 9,000 hours of service. Many UV systems have a controller that indicates when it's time for a lamp replacement.

Never touch a UV lamp glass with your bare hands. Oils on your fingers can cause hot spots on the UV lamp and shorten its life and decrease its effectiveness. Use a soft clean cotton cloth or clean cotton gloves to handle a UV lamp.

How long does UV light take to purify and clarify water?

The UV water purification process is actually very quick. As water flows through the UV chamber, bacteria and other waterborne microbes are killed within seconds. The amount of time it takes to purify your pond or aquarium would very much depend on the flow rate of water through the system, and the ability for bacteria to multiply before hitting the UV.

In periods of strong sunlight for example, algae will multiply faster than the UV can kill the microbes, which is why people often mistakenly assume their UV steriliser is faulty. It is merely fighting a battle against multiplying microbes and bacteria.

To browse our range of aquarium UV Sterilisers please click here.

To browse our range of pond UV sterilizers please click here.

To browse our range of spare UV lamps and bulbs please click here.

Photo credit(s): Evolution Aqua; Canva Pro Licence.
AquariumsDiseaseFish healthKnowledgePondsWater quality

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