Pond Filtration - What Pond Filtration Systems To Use

Maintaining a pond can be hard work, especially if you plan to raise fish and other aquatic life in it. If the water is stagnant, algae, bacteria, insects, etc. may eventually start contaminating it; and the air surrounding the pond can become odorous and unhealthy.

You can avoid this by setting up a pond filtration system that will keep the water and the aquatic life in it healthy and lively. While a filtration system isn’t always necessary (especially if you don’t grow anything in the pond), it is a good idea to get one installed. It will keep the water in the pond clear and free of harmful bacteria.

What is a Pond Filtration System?

A pond filtration system helps keep the water clean and oxygenated. It circulates the water and passes it through the filter. The filter captures a small portion of the dirt and debris in the water but its main purpose is to maintain optimal oxygen levels. This encourages the growth of good bacteria, and discourages the growth of algae and harmful bacteria.

Moving water also acts as a deterrent for insects like mosquitoes and flies, and they won’t breed on it, as they need still and stagnant water to lay their eggs in. A pond filtration system helps maintain the ecosystem you’ve created in your garden. Not all systems require this assistance.

A pond will eventually develop its own natural filtration system. This takes time and a delicate nitrogen cycle balance. You can start this process by introducing plenty of aquatic plants into the pond. The plants and some naturally present, beneficial bacteria will start changing the environment of the pond.

Once the plants are established, you need to introduce the fish slowly, giving the environment time to adapt to the new presence. The plants and the bacteria will eventually start to consume the toxins and organic waste in the water. This process can easily take more than 18 months. Most people don’t want to wait until that natural system is established, and take a shortcut by installing a filtration system.

Biological Filtration System

A biological filtration system looks after the water and the entire ecosystem of the pond. It keeps the water oxygenated, mobile and healthy for the aquatic life in it.  This encourages a friendly environment by supporting good bacteria; and helps keep the water sparkling clear and clean, allowing you a glimpse of the aquatic life below the surface. Here’s what you need to know about this system:

How it works

In this system, the water passes through the filter and is oxygenated. While the filter removes some of the suspended particles in the water, it doesn’t address all of it. That responsibility is left to the natural, beneficial bacteria present in the water. They break down the toxins produced by dead and decaying organic matter as well as waste like fish faeces and excess food.

What Role does Bacteria Play?

The good bacteria will break down the ammonia present in the water and turn it into nitrite. The latter is also dangerous, and another type of beneficial bacteria will break down the aggressive form of nitrite into a benign form that can be absorbed by the plants. In small quantities, this nitrite isn’t harmful to the fish. This cycle will keep the water free of harmful toxins that can harm aquatic life.

How Much Time Would it Take?

The natural process takes about 18 months but a filter can reduce this time to six weeks. You need to allow at least that much time for the good bacteria to colonize the biological filter. You can test this with the help of a water quality kit. Once you’re certain that the water is healthy, you can start adding fish to the pond.

Capacity of the Filter

The size of the filter you choose depends on the size of the pond and the fish population. If you have a large pond with a larger number of fish, you need a bigger filter. Maintaining a healthy environment in the water is all about balance. The filter should be able to support enough bacteria to maintain the quantity of water in the entire pond. You also need to consider the amount of sunlight the pond receives.

Excessive sunlight can cause excessive evaporation and increase the quantity of toxins in the water. Unless you plan to create a natural filtration system, you need to install a filter in your pond. Even if you don’t intend to add fish to the pond, it’s a good idea to install a filter; it will keep the water and the surrounding environment healthy.

Ultra Violet Clarifiers

Ultra violet clarifiers need to work in conjunction with biological filters. This device will address the problem of green, algae-filled water. You can purchase a filtration system that has both systems, or buy a standalone clarifier that you can add to your existing biological filter. However, the clarifier can’t replace a biological filter. It needs to be present in the water to keep the pond healthy.

The UV clarifier is designed to address the algae problem. The water is pumped through this system, where it’s subjected to intense ultraviolet rays. The rays will cause the algae to clump together and form a solid mass. The water with clumped algae is then passed to the biological filter. The helpful bacteria present in the biological filter will break down the algae, entirely eliminating the problem of green water.

You need to consider the size and the population of fish in the pond to choose the right filter. If the pond is big and has many fish, you need a big UVC to handle the load. If you have a small pond, you can choose a small UVC.

We recommend seeking advice from professionals. They will consider the size, the stockage, and the sunlight levels of the pound and recommend the right filter size to you. It’s vital to choose the right biological filter and ultra violet clarifier. If you choose the wrong size, the water can become unhealthy and risk the life of the fish and plants in the pond.