Pond Chlorine Filters

Many people are installing ponds as part of their landscape. One important element is the need for proper pond chlorine filters. With so many different types of filters, choosing the one you want can be confusing. The main types will be discussed in this article.

Bio filters sit at the outside edge of the pond. They are visible, but they can be disguised by landscaping or other means. They use a submersible pump to force water into the filter’s inlet. Gravity then carries the water out and back into the pond.

Biological filters usually filter with use of a foam pad or multiple types of pads. Carbon impregnated pads and polyester grab on to bacteria. Some of these filters come with a UVC light built in or an option to add one on. These filters can be referred to as bio, mechanical or gravity fed filters.

Pressurized Filters

Pressurized filters are popular because they can be partially buried and concealed. They also have pads like the bio filters filled with different media. Some models offer a UVC light option as well. The difference between these and the previously mentioned bio filters is that they are clamped and sealed.

When the submersible pump forces water into the filter inlet, pressure builds within. The water can then be run through tubing to any desired water feature such as a waterfall or stream. Many of these filters also have a backwash feature which allows you to flush the waste from the filter. You can then divert it out of the pond where it can be used to water a garden

Up Flow Filters

Up flow filters are large boxes that have been designed to thoroughly and quickly clean your pond water. They are very efficient and usually installed by a professional. They most often use a polyester filter bag with a filter media that you add.

They can be used with a submersible or external pump. As the water is pushed up through the media filter it ends in a waterfall or tubing of your choice.

Bead Filters

Bead filters are on the high end of the filter market. They are very efficient and convenient at filtering pond water. They are often the choice for high quality Koi ponds. Bead filters are usually able to be buried so they are out of sight. They can handle a large capacity ecosystem easily.

Bead filters are barrel shaped and filled with media beads. These beads allow the propagation of healthy bacteria. They add up to a large surface area for absorbing harmful bacteria. They are easily backwashed by a lever or an internal jet system. They can handle a lot of pressure also.

Filter Size

The size of the filter that is required is dependent on various factors. The amount of sunlight, the temperature of the water, the pond’s stocking capacity, the feeding habits of its inhabitants, amount of waste and the water chemistry all affect the size of the filter required.

An effective filter will produce clean, clear water with only several cleanings per year. One important factor in a filter’s efficiency is the surface area of the filter media. A larger area will increase the filter’s function. A properly sized filter traps debris, prevents cloudy water and maintains a healthy, balanced system.


The pump needs to be strong enough to efficiently circulate the entire volume of water through the filter every few hours. The farther and higher the pump has to push the water through the filter the more resistance it encounters and the less water it can pump. The force of gravity also has a negative impact on a pump’s output ability. Pumps are rated by the amount of water they can pump without any resistance.

When it comes to pumps, the gallons per hour rating are more important than the pump’s output pipe diameter. Do not undersize the plumbing or you will decrease the pumps output capability. As the water travels through the plumbing, it encounters friction which also diminishes the output. Try not to have too many curves and angles in the plumbing. Again, under sizing the pipe or tubing connected to the pump and filter will decrease the pump’s efficiency.

If you have a waterfall in your pond, you may opt for multiple pumps. One pump can be used for filtration and a second pump can be used for the waterfall. In addition, this way there is a backup should one pump fail.

When installing your own filtration system in your pond it may be a wise idea to consult a professional for advice on what type and what size pumps your pond requires.