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Pond UV Lights: Why They Suck And What’s Better

Keep Your Pond Cleaner And Healthier For Your Maryland, DC, Or Northern Virginia Home

Pond UV lights can be used to keep ponds clear of algae, but they aren’t the best tool out there. These lights only work on certain types of algae and they only clear the algae. You can find much better pond equipment than UV lights for keeping your pond clear and healthy, like the Ion-Gen.

Pond UV lights in a filter

This Just Isn’t Working!

“Why is there still algae in our pond, Bobby?” Dawn sighs.

The pond UV lights are supposed to take care of the algae and clear the water, yet there is still algae in their backyard pond. The green soupy-look is gone (thankfully) but not all of the algae is.

Pond UV lights can get rid of only some types of algae

Bobby has no idea either. He can still see the little strings of algae waving to him as they hug the rocks on the sides and bottom. 

“I think we acted too quickly without doing enough research,” he finally says. Dawn agrees and the couple decides to try and find out what’s going on with their pond UV lights.

Why Pond UV Lights Don’t Work Well

For what it’s worth, UV lights in ponds do what they’re supposed to: keep the pond clear of algae. But, it’s only in certain conditions.

“Uhp, well I guess we didn’t meet these conditions then,” Bobby points out.

The algae has to flow in front of the UV lights for them to work. This means you’ll either need a lot of lights or more than one type of filtration.

You pond also has to have the right speed of water flow. If it’s too fast the pond UV lights won’t work. Getting it to the right speed may increase the cost of a pond.

Clear is clean, right? Ponds have more issues than just murky water. They also have dead organic matter like leaves and muck filling it up that can make it dirty. UV lights don’t purify the water either so it may be unbalanced and harmful to any fish and plants.

“So that’s why our pond hasn’t completely cleared,” Dawn realizes.

*Pond UV lights can also be a pain to clean and hard to know when to replace.

“Well, what can we do then?” Bobby asks.

Better Pond Filter Options

The couple can always install an Ion-Gen system (our favorite).

Ion gens work to keep water clear and clean

The copper IonGen G2 gets rid of green water, excess algae, and bad bacteria throughout the pond, not just where it sits.

“That sounds a lot better than pond UV lights,” Dawn points out.

The couple can also install other filters if they don’t already have some (we build them into all of our ponds to help them take care of themselves).

These can include a biofalls, a water purifier that’s also a waterfall. It uses beneficial bacteria to clean the water. Skimmers are a filter that collects leaves, sticks, and larger debris.

They do need periodic cleaning but they’re worth it because they do so much more than UV lights.

Dirty skimmer and filter in need of fall pond care
Dirty skimmer and filter in need of fall pond care

The couple can also install other filters if they don’t already have some (we build them into all of our ponds to help them take care of themselves).

These can include a biofalls, a water purifier that’s also a waterfall. It uses beneficial bacteria to clean the water. Skimmers are a filter that collects leaves, sticks, and larger debris.

They do need periodic cleaning but they’re worth it because they do so much more than UV lights.

Their Next Steps

“Well, I think we should try the Ion Gen thing next. If that doesn’t work we may need to add filters directly to our pond,” Bobby says. Dawn agrees so the couple sets out to find an Ion Gen for their pond.