Why an Air Pump is an Excellent Idea for a Garden Fish Pond

Everybody has seen an aquarium where a thin column of bubbles rise to the surface and escape. Did you ever ask what's the point of this? If you did you probably thought it was for the benefit of the fish in the aquarium and to a point your were right but probably not for the reasons you think.

As the bubbles of air in the column rise to the surface some of the oxygen contained in the air bubble (remember air is only about 20% oxygen) is transferred to the water surrounding the edge of the bubble. However this process is quite slow and that's why it takes massive quantities of small bubble to transfer a meaningful quantity of oxygen to the water. But why transfer the oxygen anyway?

The oxygen dissolved in water is consumed by living creatures in the pond including fish and most importantly the bacteria in the bio filter. The filter bacteria use the oxygen to convert poisonous ammonia that is released normally by the minute to minute metabolic fish breathing and urinating process. These bacteria are present in a filter in their many millions and needs large amounts of oxygen to transform ammonia ultimately into nitrates through a process called nitrification and discussed in this article here ... What really happens in a fish pond filter every day all day. So just like for you and me oxygen keeps everything (not just fish) in a balanced pond alive and, hopefully, thriving.

Not Too Many Fish and More Plants

If you keep a lot of fish in your pond, few plants and if you also feed the fish too much food then your pond will certainly benefit from buying an air pump. You can reduce the need for oxygen replacement by feeding less, lowering fish stock density and increasing the quantities of oxygenator plants used in your garden pond. Talking of feeding it always best to feed less and higher quality koi food ... read this article on how to save money on buying koi food if you need convincing.

In summer on warm muggy windless days oxygen deficiency becomes a very serious, death threatening possibility, and is why all serious koi pond keepers blow massive quantities of air into their ponds, waterfalls and filters. If fish die overnight in warm sultry conditions then suffocation must be a prime suspect for the casualties.

It's a fact that you will transfer more oxygen from a small bubble than you will from a big bubble and is reason why an air pump runs in conjunction with air-stones and not just through an open ended pipe.

In selecting an air pump you need to review the manufacturer's data quite closely ... in particular note the depth at which an air pump can operate.

It's a good idea to blow air into your pond filter if you can. In this regard there has been an exciting pond filter development by Hozelock just released. The unit is called the "Trinamic" and this new filter is going to revolutionize pond keeping for the medium sized garden fish pond. Read about the Trinamic here ...

A pond filter system that depends entirely upon air pump agitation for its efficiency is the Vortex cum Japanese Matting pond filter system (called Vortex filters). The system is described in this article following. It is favoured by all top level koi keepers. Vortex Filters | Japanese Matting is Best Filter Biomedia. Here's Why

Pond Keeping Units to Help You Convert

Now we've started to talk litres you might find this table below useful. It helps to translate one set of units to another quite easily.

Example ... 1 cu.m per minute is the same as 1,000 litres per minute or 35.32 cu.ft per min or 220 imperial gallons per minute.

Factors to be aware of with all pumps. This is a good page to read before you buy any pump.