I run a similar, though not as intricate, system. The name for the method of filtration is "reverse flow" filtration. I use it on many of my tanks and have for years. I use Perfecto under gravel filter plates and Marineland powerheads. I use the Marineland 660r primarily, but do have tanks using the Marineland 550 and 1140 with the power filter adaptors. I have been a staunch advocate of this for many, many(at least 20-25) years.
Here is a link to the powerheads: http://www.petsolutions.com/Penguin-...68550+C42.aspx
Here is a link to the adaptors: http://www.petsolutions.com/Reverse-...86861+C42.aspx
There is a problem that he did not address. I would take it he is using this method in a cichlid tank judging by the crushed coral he is using as a substrate and the forum in which it is posted. Cichlids are master
excavators. They seem to move the gravel substrate just to be moving it. This can expose the filter plate. Whether the ugf is being used in conventional fashion or with reverse filtration, it provides a place for decreased resistance for the water. If the plate is exposed, more water will enter/exit, depending upon the system, through this "gap".
This is the reason I use Perfecto plates. These plates in a cross-section look like "W". I fill the "troughs" with substrate and glue a cheese cloth-like material to the "peaks" using a silicone adhesive. The "master excavator" can only dig so far. The integrity of the plate and system is never compromised.
Another thing that the author brought up that I do agree with is the fact that this method is not a "stand alone" system. I use power filters, both external and internal, and canister filters in all of my big tanks. Event the 29g tanks using this method have a power filter(s) used along with the reverse flow method. It is a must in my opinion. The sponge filters alone cannot handle the job as effectively as a "multi-layered" system.
I use this system in tanks from 29ga to 300g and swear by it.
The system you linked is WAY too complicated for me.