Garden Pond Filters

The Natural Garden Pond

There are many arguments pro and con about the advantages of natural bio mechanical pond filters vs. commercial filters. It really depends on what you want from your pond and how much you want to be involved in it's life and maintanence.

Swimming pools use mostly Mechanical Filtration System. The component combination includes a water pump, filter media either diatomaceous earth, sand or some othe mechanical means of removing impurities.

Since plants and fish will become an important part of any garden pond, you will have to deal with fish waste and decaying plants. A mechanical filtration system will not work alone, adding biological or bacterial filtration can produce much better results.

Bio-Mechanical Pond Filtration System: Lava rock, foam or gravel can act as a home for nitrifying bacteria, by moving the pond water through this it will speed up the process of converting ammonia to harmless nitrate.

Natural Filter System: But if you want a traditional approach, consider a natural filtration system, which utilizes aquatic plants as a filter. That is why it is also referred to as a bio filter. Plants perform the total filtration, not just part of it.

If you want to have Koi in your fish pond, a filter like this will be neccessary to keep the pond clean. Koi are very rough on plant life. If you have Koi in your pond you will be limited on the kind of water plants that can be included.

the benefits of plants filtration:

Aquatic plants consume toxic compounds such as ammonium, nitrite and nitrates. fish will be better protected.
Aquatic plants remove toxic heavy metals and other pollutants from the water. Fish will benefit from this as well.
Aquatic plants provide surface areas for bio-films and beneficial bacteria. Aquatic plants improve water quality.
Aquatic plants help control algae. They not only consume nutrients but also Aquatic plants emit allelopathic chemicals that inhibit algae.
Aquatic plants oxygenate the water. They provide more oxygen than they consume.
Aquatic plants remove CO2 from the water. Excess CO2 can cause fish distress.

Natural plant filters can be any shape, and they only needs to be between 10” and 18” deep. Calculate total surface area of the main pond you are going to filter, Calculate10% of surface area. That is the size of the plant filter surface area required.

Use treated lumber, cement blocks, Redwood or Cedar timber for your frame. Use arubber or PVC liner for the pond filter. Shape the bottom to form a low point where a bulkhead drain will be installed. The bulkhead drain will assist in flushing sediment from the pond filter. Face it with stone, or hide the walls with plants, and your ready to go!

Garden Pond Filters