Friday, June 17, 2011

Mechanical and Biological Filtration

The filter is important in keeping your pond water free of chemical pollutants and crystal-clear. Two major types of filtration include:

MECHANICAL POND FILTRATION: It is the physical removal of debris from water using materials that trap large and small particles. Polyester Pre-Filter Pads last longer and filter better than other pre-filtration products, even after a few cleanings.

If your pond is ornamental or you are looking for a pre-filter for your pump, a mechanical filter will be best to choose. The filter is designed to separate large particles and debris from the water passing through it. This is an advantage when protecting a pump. When it is run through a mechanical filter, water will not be treated and will retain toxins or harmful substances it had before entering the filter. Because of this, mechanical filters are not recommended as the only source of filtration for a pond that contains fish. Most filters available on the market feature some degree of mechanical filtration besides their specialized function. Skimmers, canister filters, and prefilters all rely on mechanical filtration.

BIOLOGICAL FILTRATION: This is where your pond filter provides an area for beneficial bacteria to grow on special media. This kind of bacteria removes harmful pollutants from pond water. The beneficial bacteria convert poisonous compounds like ammonia and nitrite, to a less toxic nitrate. Nitrate, the end by-product, is used as a food source by aquatic plants. As you may know, this continuous process is the nitrogen cycle.  Biological Pond Filtration uses specific bacteria to break down waste products to less harmful substances. There are two stages in the breakdown of ammonia, each involving different kinds of bacteria. The first stage is the breakdown of ammonia to nitrite by nitrifying bacteria, most important is Nitrosomonas. The second stage converts nitrite to nitrate by Nitrobacteria. Both of these kinds of bacteria are aerobic. Sediment build up in the filter will deplete oxygen levels, so it important to keep sediment at a low level by using a settlement chamber first and by cleaning the filter out occasionally. Do not use tap water because chlorine will kill the bacteria.

There are many things to put in the filter such as gravel, matting, hair rollers, foam, and Canterbury spar. All of these provide surface for bacteria to thrive on. A biological filter will take weeks or months to mature. Cultures of nitrifying bacteria are available and will speed up the process.

Back to (Our Koi and Pond Information Site)
Back to (Our Koi and Pond Information Site and Online Store)

No comments:

Post a Comment