pond bio filter Designs and Ideas

It can be very simple to make your own pond biofilter but at prices available from right outlets selling the correct type it is probably not worth the effort. The pleasure from your pond, the health and size of your fish, the appearance of your plants is based upon your biofilter working optimally. There is no fixed shape, size, location or anything else for a biofilter. Always remember that any biofilter is just a place where water, fish waste and oxygen all of which are dissolved in the circulating pond water can meet the bacteria responsible for converting this waste (the waste is actually food for the bacteria) into non toxic chemicals that remain dissolved in the water. The more oxygen in the pond water the better because then the pond filter bacteria are lively, strong and hungry.

Work the principles into your own design if you want to make one yourself. Who knows maybe one day you will be a designer of biofilters. This page is meant to give you a few clues. Take a look at the picture below drawn by my good friend and fantastic landscaper/author, Peter J May.

box pond filter with brushes This picture shows what is essentially the design of the typical black box garden pond filter.

  • Top outlet to pond bio filter (good) ie UPFLOW. It is easier to get a good spread of oxygenated water across the biomedia by allowing water to flow up through the pond filter biomedia
  • Brushes for solids removal in bio filter before water reaches biomedia bed where bacteria live. This is good pond filter design criterion but not totally necessary, since you can use virtually anything to do this job so long as you do not restrict water flow through the pond filter.
  • Space at bottom of pond bio filter for solids accumulation (take notice of plug at side of filter for draining it). The solids that accumulate in the pond bio filter MUST be removed regularly so a drain plug or even better a drain valve onto the pond filter makes this important job easy and quick.
  • Tray for placing filter biomedia onto. This biomedia is the place where the good pond filter bacteria live. This is where the action of converting pond fish waste takes place ... the more biomedia in the pond filter the better because this means more places for more bacteria to live and feed and the more bacteria there are the better the job done by the pond bio filter.
  • Foam at the top of this pond filter creates more solids filtering capacity and more biomedia capacity. The bacteria live in the tiny holes and on all surfaces inside the pond filter and all its components
  • Water is sprayed onto top of brushes ... it is important that the pump runs 24/7 so get good reliable low running cost pond pump here

Copy these principles and you will have a good garden fish general purpose small to medium sized pond filter. Heres a view from another angle

If you use a pond filter with Alfagrog you do not need brushes in your pond filter

Take a note how pipe is connected to filter from the pump

Make sure you get the muck out ....

Information on Alfagrog ... Without getting too technical this means that 1 litre of Alfagrog can hold the same amount of bacteria as 200 litres of plastic tubes. In other words a box using plastic tubes needs to be 200 times bigger in volume than one containing Alfagrog to get the same biological performance.

Good Pond Filter Design Principles Summary

A filter will do a good job if there is a way removing solids effectively and of colonising large surface areas of bacteria that are able to intimately contact the water containing the waste products pumped through the system and if there is continuous flow of oxygenated water through the biofilter we tend to use the word filter as a short version of biofilter. The more surface area that can be incorporated into a filter the better. An attempt (albeit a basic attempt) to achieve this is by placing hollow tubes of rough plastic inside the filter box. Other attempts include the use of orange bags, lava rock, tubes, and even hair curlers.

Alfagrog is called Supra in USA Alfagrog is called Supra in USA and can be bought here ... it is best all purpose media for small to medium ponds . Alfagrog looks a bit like cinders, it is lightweight, comes in different sizes and you can literally blow through it because it is so porous.

For any pond product in USA click this link For widest range and best prices for all pond and bio filter products in USA

For any pond product in UK, Ireland and EEC click this link ... Get pond pumps, pond bio filters, UV and other pond equipment direct from UK's lowest cost supplier including range of OASE and Hozelock top sellers

"The Complete Pond Solver" by Tony Roocroft ...  2005 Edition. Essential reading for anybody who wants or has a garden pond. Get 12 Excel pond calculators free as well as "Water Lilies and Pond Aquatics" ebook also free