Pond Filters for Your Water Garden

Why do I need a pond filter?

Pond filters perform two vital functions for your pond. First, the pond
filter will clean the pond water make the pond clearer and healthier. But the main purpose of the pond filter is convert toxins in the water into substances that can be absorbed by the ecosystem. Ponds without filters, or that have poor or undersized filters, are usually dirtier and may have problems with water quality.

How does a pond filter work?

Most pond filters provide at least two of the three types filtration. These are:

Biological Filtration is performed by beneficial bacteria that break down ammonia in the water caused by fish waste, uneaten fish food and other naturally decaying organic matter. Nitrosmonas bacteria convert the ammonia into nitrites. Nitrobacter bacteria then convert the nitrites into less toxic nitrates. Aquatic plants then absorb the nitrates as food.

Mechanical Filtration is simply the removal of suspended particles from the pond water usually by a foam or polyester mat or pad in the pond filter. Generally the finer the media, such as foam, the more particles will be removed. But beware, the finer the media, the more maintenance the pond filter will require.

Chemical Filtration uses chemical processes to remove toxins from the pond water.

Zeolite is commonly used in the pond filter to trap ammonia from the pond water. Zeolite does become saturated with ammonia and should be "recharged" every two to three weeks. Simply soak the zeolite in a salt bath over night and rinse thoroughly. Salt causes the zeolite to release the captured ammonia and regain is effectiveness. Always remove zeolite from the filter before applying salt to the pond to avoid a deadly ammonia spike in the water.

What common mistake should I avoid when selecting a pond filter?

The most common mistake pond owner's make is selecting a pond filter rated for just at or below the pond's volume. By stretching the manufacturer's specifications, which may already be exaggerated, the pond filter may simply be too small to properly clean and filter the pond. The result will be a dirty, unhealthy pond with a pond filter that requires frequent cleaning. Always oversize the pond filter so that the pond will be cleaner, healthier with a pond filter that will need little maintenance. After all, who wants a dirty pond filter that needs to constantly be cleaned?