How to Achieve Proper Aeration and Filtration for Your Harrisburg, PA, Pond

A garden pond with exotic floating plants, the soothing sound of running water, and a few fish can transform a backyard into an oasis. But keeping a pond healthy and attractive requires special care. Here is how to achieve proper aeration and filtration for ponds in Harrisburg, PA.

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Mechanical and biological filtration eliminates and processes fish waste, runoff from lawns, uneaten fish food, decaying plant matter, and debris such as leaves and pine needles. Keeping debris out of the pond is the job of the mechanical filter; the job of the biological filter is to maintain nutrient and pH levels that support fish and plant life.

Filtration systems are commonly used together to keep pond water clean and healthy.

Mechanical filters (pond skimmers): Filter mats, placed horizontally or vertically, trap larger debris and sediment before it sinks to the bottom and creates a decaying sludge. They do the heavy lifting of ensuring that the pond is free of silt, leaves, and other debris. The pond skimmer comes in two types: floating skimmers and box skimmers. Box skimmers are easier to clean out and maintain, so they are more common. Large debris is trapped in the filter, and water is pumped through underground plumbing to the biological filter, which will remove impurities before the water is pumped back into the pond.

How to Achieve Proper Aeration and Filtration for Your Harrisburg, PA, Pond

Biological filters: Pond waste is broken down by bacteria into material that fertilizes the pond’s plant life. A biological filter receives water after it has been filtered by the mechanical filter (pond skimmer). As the biological filter fills up, it is purified, and then overflows from the filter into a man-made waterfall. As the water cascades back down into the pond, it creates the aeration necessary to keep the pond water circulating. For biological filtration to work, it is important to create a good host environment for the bacteria: In most cases, this means a layer of gravel on the bottom as well as rocks along the water’s perimeter that bacteria can cling to.

Sterilizers: These use ultraviolet light to eliminate living microscopic particles. If the mechanical and biological filters are doing their job, sterilizers are generally not necessary. (Do note that filters must run 24/7 when the pond is filled with water.)

Aquatic plants: This is another, natural way to help filter pond water. Plants absorb toxins, filter sediment, and reduce the nutrient levels in the water, thus contributing to a healthy pH and lower nutrient levels to help prevent algae growth. On the plus side, plants also provide shade, protection, and food for fish, as well as for other small wildlife that will also enjoy the pond.

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A pond that is not aerated quickly becomes stagnant and swampy, which will then attract mosquitoes and other water-breeding insects. Aeration is achieved when low-circulating water (typically the bottom and any corners of the pond) is pumped over the pond’s surface to oxygenate it. A popular solution is a pump that cascades water over a small waterfall where it is aerated before flowing back into the pond. Alternatively, the pond can be aerated using current jets, external pumps, or aerated biofilters.