Some people may want this to clear larger ponds.

[peter hillman]

Or is it snake oil?
http://reno.craigslist.org/grd/5840469151.html

 

[Meyer Jordan]

They are showing more than one product. The use of surface agitation to oxygenate water columns is nothing new. There are many configurations of this method available. The concept is not 'snake oil', but these particular products may be.

 

[budgenator]

Real or snake oil, No it's all the above. Paddle-wheel agitators aren't new and aren't particularly energy efficient. The photos are probably best results rather than typical results. If you had a bigger mud pond with those problems a submerged aerator fed by a compressor would do the same job use less electricity and should cost less.