Homemade Pond Filters

Homemade Pond Filters

Homemade pond filters serve the same purpose of filtration as that of the commercially available varieties, but in a biological manner. You can build your own pond filter by using a large rubber pot, some lava rocks, mesh bags, and a pond pump.
Gardenerdy Staff
Man Building Artificial Pond
The beauty of a landscape design is incomplete without the addition of a water feature. The same is true with gardens; supplementing them with ponds or any other water structures always adds to the visual appeal. Building a pond is not the issue, the concerning factor is its maintenance. Many of the gardening enthusiasts do not even consider a garden pond, mainly because of the cost of buying the essential components, like pump and pond filter. If such is the case, an affordable alternative is using homemade pond filters.

Build Your Own Filter

The basic principle of a pond filter is to create a healthy environment for the inhabitants of the pond, such as plants, fish, and other organisms. For providing such a condition, availability of adequate amount of oxygen is the key factor. Overall, the water chemistry of the garden pond keeps on changing due to environmental pollutants and fish wastes. A pond filter does not remove the water contaminants physically, rather it acts as a biological substrate for the beneficial bacteria that convert the nitrites, nitrates, and ammonia into usable forms for the plants and fish.

In order to build your own pond filter, you will require a large plastic container or grow pot (at least 3-4 gallon), mesh bags, large rocks (preferably lava rocks with large surface area), and submersible pond pump. The size and amount of rocks depends upon the size of the container and pond. Hence, larger the pond, the more lava rocks you will need. Also, the rock surfaces may be dirty, so cleaning should be done prior to using them for making a pond filter.

First of all, fill the clean lava rocks in the mesh bags. Though they are lighter than other rocks, make sure that you add only the amount that a mesh bag can hold. The rocks will also become heavier after deposition of wastes and accumulation of bacteria. The weight of rocks in the mesh bag should be such that the bag can be lifted easily. For convenience, add the rocks in the mesh bag, dip it in water and check whether you can pick it up easily or not. Accordingly, you can make use of three or four mesh bags for adding the lava rocks. Once you have completed adding the lava rocks to the mesh bags, keep them aside.

The next step is positioning the pump and tubing (if any). Put the pond pump at the bottom of the container, preferably on the side. Doing so will allow easy adjustment of the attached tubing and electrical cord, so that they stick out of the container. After correct fixation of the pump and tubing, gently place the mesh bags containing the lava rocks on the top of the pump. With this, you have completed building a pond filter at home.

Place the pond filter in the water and turn on the pump. The water drawn by the pump is filtered through the rock layers. Within a few weeks, bacterial layer will develop on the rock surfaces, which in turn maintains the nutrient and oxygen level in the pond. Thus, your homemade pond filter works as a perfect biofilter system and creates a better environmental condition for the plants, fish, and other inhabitants of the water body.