Oxygen - Where to put the air in a Koi pond

Anywhere reallly...

Nigel Caddock NI

Where to put the air?

The simple answer is it doesnt really matter. There are of course numerous options: turbo air domes in-pond diffusers or in the filters, our experience is simply that the only relevant number is the level of system DO. While its true that the nitrification process occurring within our filter systems consume large quantities of air, it makes sense to deploy air in the filters. Air bubbles relax Koi so turbo air domes are great for that. Add their ability to mix and the low pressure regions they create which in turn assist bottom drain function it makes sense to include them.

One development that has emerged in the great what size air line to use to feed air domes debate. TOPTIP - Once again Sean Hunter of Reflections/Topponds fame came up with the answer - neither! What the intrepid Mr Hunter did was feed the dome with a 1 pressure pipe with connectors t each end and then pressurise the 1 pipe with air! Absolutely brilliant.

Less back pressure on the air pump, enhanced performance of the dome and no crappy air line to kink, get blocked, become detached or perish! Best of all like all great solutions - absolutely simple.

When putting air into filter chambers we need to consider that air also creates pressure. For example by placing them in traditional filter transfer ports which is good in one way because all the air has to flow past it, there is a risk that the air creates enhanced back pressure and a mini air lift effect, this in turn results in the water flowing from filter to filter being impeded and water levels in downstream chambers can get too low and even starve end chambers. No big deal but it needs to be considered. In contemporary systems much of this guesswork has been designed out.