Aquatic Ponds

A Pond UV Light is a great way to achieve crystal clarity in from pond water. It does not take the place of a biological or mechanical filter, but it kills tiny algae that these filters cannot remove.

Single-celled green algae are present in every pond. These tiny plants are suspended in the water. They do not anchor themselves to rocks or the sides of ponds, they do not rise to the surface, and they do not settle out to the bottom of the pond. Algae are the lowest link of the food chain for many aquatic organisms, and in small amounts are good for a pond. Unfortunately, algae don’t limit their growth to suit a pond owner’s sense of aesthetics. When single-cell algae grow unchecked, the result is green water.

Mechanical filters removes debris and many types of free-floating algae, but the single-celled algae that cause green water are just too small to be trapped by the filter media. When the algae die, however, they clump together into particles large enough to be filtered away. Chemicals can be added to pond water to kill algae, but following directions and using a pond air pump for extra oxygen is recommended. Decomposing algae will starve a pond from oxygen.

UV Lights for Ponds are essentially a clear pipe surrounded by UV, or ultraviolet, light bulbs. As the water flows through the clear pipe, it is exposed to the ultraviolet light radiating from the bulbs. The light is very intense, and it kills microscopic organisms in the water. As the single-celled algae die, they form clumps that become large enough for the regular filter media to trap and remove from the pond’s circulation.

As with biological filters, a UV pond clarifier must be sized appropriately for a pond. A rule of thumb is that half of the volume of the pond should pass through the clarifier every hour. The quicker the water flow the more watts of uv will be needed. With a pond uv light the water must pass through slowly enough for the bulbs to irradiate and kill the algae, but the flow must be high enough to supply the biological filter.

Pond clarifiers do not leave any harmful residue in the pond water, and the water never comes into actual contact with the bulbs. The bulbs must be replaced periodically. Once you notice the water is not as clear or to your liking then it’s time to replace the uv bulb.