I have to say, I am very impressed.
I was called out to a site that had an Orenco Secondary Wastewater Treatment System installed. It was the Advantex AX-20 setup. This was a medium-sized home that had not-so-good soils and therefore the choice was made to install a treatment unit (after the septic tank and before the field). These types of units treat the effluent to an extremely high quality before sending it to the final treatment field (or mound). The effluent is nearly colorless and clear.
However, in order for these treatment units to maintain the high quality of treatment, regular annual maintenance MUST be done. It would be much like owning a Ferrari or a racecar.... if you aren't changing the oil regularily you will have problems.
In this particular situation, the homeowner did not take responsibility and was not on a maintenance contract, and the unit had not been maintained in nearly 2 years. I was worried about what I would find ..... as you can imagine, things can get unsightly without proper maintenance.
However, I was surprised to find how well this one looked. The pump filters were extremely dirty, however the hanging "curtains" inside the unit (where most of the treatment is accomplished) where surprisingly clean, considering the circumstances. Many times, even after a year, the curtains can be completely covered in a biofilm (slime) that needs to be cleaned.
Now, I am not promoting or advocating the idea that its OK to skip required maintenance because it is both against regulations and you could lose your warranty. But, my point here is that this system was obviously sized correctly and the homeowners, although skipping maintenance, did not abuse the system and this allowed this setup to operate outside of its standard maintenance parameters.
Orenco is a great company, with great products. I've had the opportunity to visit their factory in Oregon and see firsthand the technology and people behind it all.
Many of my designs include these AX-20 setups because they have predictable, rock-solid performance and Orenco offers 1st class support, either directly from HQ or through their distributors here in Alberta such as Alberta Wilbert Sales.