In order for the nitrogen cycle to take place in your biofilter there will have to be oxygen rich pond water, pond biomedia and a readily available supply of ammonia.
Ammonia is nearly always present in garden ponds as it is released into the pond water by aquatic life as part of their metabolism. It is also present to a lesser degree from decomposition of leaves and other debris on the pond floor.
What Components Do I Need For My DIY Pond Filter?
Before you start your project take a look inside a commercially sold box type pond filter to get some ideas. Homemade pond filters are easy to make and will save you money. You will need the following pieces of equipment:
- Flat open cell foam or stiff bristle brushes or both.
- Inlet pipe, outlet pipe and overflow pipes back into your garden pond.
- You will need biofilter media of some description for the beneficial bacteria colonies to live on. You will often see the following filter media in commercially sold filter boxes: plastic coils, plastic tubes and plastic balls.
- A suitable filter box to store the components in. There are different sized black boxes to use as the container for your diy pond filter. Please be aware that it is not the size of the filter box that determines the volume of pond water the pond filter can effectively filter; it is the choice of biological pond filter media used.
How Do I Make A Home Made Pond Filter? - Stage 1 involves trapping leaves and other organic matter from entering into the biological filter chamber by using flat open cell foam or stiff bristle brushes or both.
- Stage 2 involves ensuring that pond water flows or pours over the pond filter media (up or down the biofilter media). This pond filter media must be kept wet and oxygenated at all times by recirculated pond water.
- The box type pond filter operates under gravity conditions and generally is placed at the highest point in the pond system. Box type filters are sometimes referred to as gravity fed pond filters or gravity discharge pond filters.
