A pond can be a real centrepiece for a garden, helped somewhat by the various ambassadors of the animal kingdom who will come to visit your very own oasis. What you may not realise is that a pond is in effect, a miniature eco-system, with each of the varying animals and plants all dependent on one another. Be it animal waste, or waste from dead or dying plants, this organic waste will sink to the bottom of your pond and release harmful toxins which will then have negative repercussions for the safety of your pond. Having an effective filter therefore, becomes a top priority. This article is designed to provide you with some ideas as to how to keep your pond purified using only natural means.

Biological filters all work around the same process, utilising specific bacteria that will break down and neutralise the organic waste material, as well as the toxins that are created as a by product.

For those who are more scientifically inclined, or just idly curious, this “good” bacteria coverts the chemical ammonia which is produced by the decomposition of the organic waste material, into the nitrite.  The nitrite (which also happens to be harmful) is then further broken down into nitrate, which is relatively harmless in of itself and which will ultimately be absorbed by the plants present in the pond filter anyway.

Because it is plants that will be absorbing and neutralising the final product, nitrate, it is imperative that you have a high plant presence, at a rough estimate, around two thirds of the pond covered by plants. The best type of plants to use are the so called oxygenators, make sure to add aquatic soil rather than ordinary soil, because ordinary soil is too rich in nutrients meaning that you will spend more time than you will want removing weeds from the pond.  If your pond is murky and has a slimy residue, then you have not well-balanced the pond eco-system, because you have high algae growth.  The best plants to use for as oxygenators are Blue Lotus, Water Lillys, Papyrus, anacharis, cabomba, hornwort to name but a few. The oxygenators will take the nitrate and the CO2, and exhale oxygen which is a must for your animal friends.

Remember, balance is key for a successful, thriving pond, with a little experimentation and a good deal of patience you will have results in no time!