I am an expert, and the specs as Burgermeister suggested will allow the compressor to work fine in your pond at a depth of 12'. In fact, at 12' you are at around 10.6" Hg. Even if you have to add 1,000' of 1/2" pipe from the compressor to the diffuser, you only add another 1.2 psi of friction loss.

*****CAUTION******** Since this pond aged and has NEVER seen any circulation from the bottom up, you MUST follow a start up proceedure. Secondly, there is most likely a large amount of nutrients that are blocked by a thermocline and by removing this thermocline, you may find that intially you will have an algae bloom larger than you have had in the past. This will cease once the biological and chemical changes are met in the pond and the assimilation capacity (the pond's ablility to assimilate the nutrients in it) is increased.

As a side note...we too carry the 9" diffusers but are happier with the tube diffusers for performance. With a single AirPod, you will be circulating the entire volume of your pond around 4 times per day....a little bit large for your small pond. Look into a smaller diffuser like a Shallow Pond Diffuser and split it into to zones in you pond.

Best fishes!

Cary Martin
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