Now the pond build was finished I had to consider what pond pump and pond filter to use. Here is a description of the thoughts and reasonings I used to come to my final decision on a pond filtration system.
Now we had a finished pond liner pond with an electrical supply alongside. The next choice was to choose a suitable pond pump and pond filter.
Perhaps the first thing you need to do when choosing any pond equipment is first to work out what pond volume of water you have and what type of pond you have. I knew we had approximately 12,000 litres of water (2643 gallons). This can be worked out in a number of ways that we looked at earlier when we looked at filling a pond liner pond with water. I knew I wanted to keep a small number of fish and run a sizeable waterfall. I also wanted a UVC light to stop the water turning green. The first thing to work out was pond pumps.
Pond pumps come in different guises. As I wanted a pump to run to a filter and waterfall it had to be a solids handling pond pump – also known as filter pumps. As the pond volume was going to be 12000 litres a quick rule of thumb is to ‘turn’ the water over every two hours. This means a 6000lph pump. But I also knew that I needed a pond pump to push water to a height of approximately 1m. This would mean 6000lph at a head height of 1m.
Another part of the equation was to decide what filter to employ. I decided on a pressure filter as I wanted to be able to hide the pond filter away from the waterfall. Fortunately large pond pressure filters are now more readily available - these offer a significantly larger filter media capacity than years prior to 2011.
Another part of the equation was to decide what would be living in the pond. Although it was designed to be mainly an ornamental water garden I thought the addition of a few fish might be a nice touch. I had thought of goldfish but given the large scale of the pond I thought they might get ’lost’ in such a large pool so I eventually plumped for the idea of stocking a few young koi which would be easy to spot. The ‘rule of thumb’ with a koi pond is to ‘turn’ the water over every hour – koi produce a lot of waste and need to be more carefully into the equation. This meant considering a pond pump producing 12,000lph at 1m head height.
The final decision revolved the choice of pond UVC light. This is much easier to make as you can’t really spoil a pond by putting in too big a light. In fact most pond filters have the UVC light built into them so prevalent have they become. A rough guide is 1watt per 1000 litres of water – but then it all depends on how deep your water is and how much sunlight it faces. I thought it best to aim for 18 watts and above.
Decisions, decisions…..The following article explains our final choice of pond pump and pond filter