NNR Jaubert's filtration system - worth it?

[journey0820]

Hi all,
I'm reading, reading and reading in hopes of setting up a successful system. I came across a filtration system and would like to get your opinions.

The method is called "Natural Nitrate Reduction" and uses a "plenum system" (stagnant area) under the substrate of the aquarium which you put in place in the very beginning.

The plenum is created by using a grid material like an eggcrate or something elevated by pvc up about one inch from the bottom of the tank. Then, fiberglass window screening is wrapped over it to keep the sand from sifting into the stagnant area. Then you add a layer of sand (2''). put down another layer of fiberglass window screening. Then add the last layer of sand (2''). The screening keeps your inverts from disturbing the bottom layers. Supposedly the trapped oxygen at the bottom creates the perfect situation for the denitrifying bacteria. Does anyone use this? Anyone have opinions?

 

[Ace25]

It sounds like a complicated DSB. I guess if you have things that really stir up the sand it would be ok, but I don't have that problem. I don't understand how that system replenishes the oxygen that you trap.. but I always see little air pockets, bubbles coming from deep in my sand. Look closely at the pic you can see a bunch of air bubbles trapped throughout the sand.

 

[Grins]

The plenium systems were common years ago, but have fallen out of favor as DSBs and shallow sandbeds with live rock and skimmers in sumps have become popular.

 

[psariandras]

I read in a few different places that no differences are noticed using the plenum system than using a DSB without one, although some sources still advise using one.

I am pretty sure that most sources instruct that the plenum is not worth it. I've asked around about this as well, and it seems that most people agree that the plenum system is not worth doing.

 

[andy1130]

Rather then just 'they work good' or 'they dont', here is a good two part scientific comparison;

http://www.advancedaquarist.com/2005/6/aafeature/view?searchterm=jaubert

http://www.advancedaquarist.com/2005/7/aafeature/view?searchterm=jaubert

 

[kcress]

Whew.. A lot of read there.

Most interesting too.

 

[Ace25]

Good summary though.

Summary:
Our experiment shows no evidence for any of the espoused benefits of a plenum (reviewed by Goemans 1999). Instead our results suggest that any benefits seen are a direct consequence of the presence of the sediments themselves rather than the void space beneath it.

Overall death rates were roughly twice as high in aquaria with shallow sediments as in deep sediment treatments. The highest overall death rates were seen in aquaria with shallow coarse sediments over a plenum, and the lowest death rates occurred in aquaria with a sandbed composed of deep coarse sediments. The treatments that were closest to the design aquarists employ for deep sandbed, Miracle Mud and Jaubert plenum aquaria had intermediate death rates. The shallow coarse sediment design that is closest to that used in Berlin systems had one of the highest death rates, and the deep coarse sediment design for which there is currently no accepted name had the lowest overall mortality. We did not test bare bottom tanks, but the data clearly suggest that the shallower the sediment, the higher the mortality rate, and you can't get much shallower than a bare bottom tank!

Experimental results were surprisingly similar between the aquarium dosing and live animal experiments. Contrary to our expectations, the presence of live animals and sediment infauna does not have any measurable effect on final nutrient concentrations in our experimental aquaria.