Jaubert Plenum

[mojoreef]

Ok folks here is round one. This is the discription and concept of a Jaubert Plenum. Take a pick and let go from here.

Professor Jean Jaubert, originally of the University of Nice, in France, was the originator of this sytem to be used as a nitrifier and a denitrifier using bacteria in both areobic and anaerobic states. Prof. Jaubert also determined through closed system experimentation that the key to unlocking the potential to the sediment was diffusion. His discovery began to materialize in the late 70's, and reached an apex in the 90's with an American patent (which was obtained subsequent to his European patents of the same system), # 4,995,980 (Delbeek, 1994).
Moving on to a correct setup and utilization of the system, an understanding of nitrogen utilizing bacteria is required. As many aquarists are familiar with the nitrogen cycle in aquaria, and that upper layers of sediment are excellent for aerobic nitrogen breakdown/utilization, they also realize that for nitrate to be effectively utilized by the bacteria (and converted to nitrogen gas), a substantial surface area of space that is low in oxygen (generally below 2 mg/L) needs to be present. Well, deeper sediments provide an ideal area for nitrate breakdown and utilization by bacteria. Thus, the Jaubert system, consists of a 4"-6" deep layer of sediment having mass resonant of that found on high energy reefs (i.e., variable sizes, with little to none smaller than 2 millimeters, Carib-Sea's Geo Marine Crushed Coral generally makes the ideal substrate, along with some large grains mixed in), which rests on top of an elevated diffusing plate (usually plastic lighting louvre/eggcrate covered with fiberglass screen to prevent sediment from falling through). The sandbed/diffusion plate rests 1"-2" above the bottom of the container/aquarium, supported by small sections of one or two inch PVC pipe.
It is important to keep the sides (below the sand line) and underneath of aquarium covered to prevent any light from entering the sandbed/plenum system itself beyond what comes through the exposed topside. Keeping all light from the sandbed and "plenum" space system prevents extra growth of oxygen producing autotrophs in the space meant for low-oxygen, nitrate utilizing bacteria. This assists in maintaining the oxygen concentrations in the plenum space at around an optimal 1-1.5 mg/L,. Some oxygen should be present in the plenum/lower sandbed, as just mentioned, in order to prevent hydrogen sulfide buildup, etc.. This small allowance of oxygen is provided through bioturbation by absolutely pivotal sanded infauna. These infauna also allow diffusion of nitrogen gas back up through the sandbed to escape the system.
Once established, bacterial metabolism produces organic acids and bacterial respiration forms carbonic acid in the local water. These processes/substances lower the pH of the sandbed and allow dissolution of the argonite substrate, with diffusion assistance from the plenum space below. The ions liberated by these actions are diffused in the display/bulk water via the same bioturbation that allows nitrogen to escape. These ions and their functions in terms of scleractinian corals and maintenance of reef-quality water. The trick to gauging the amount of ions liberated and the demand for their maintenance of water quality lies in initially monitoring the carbon/nitrogen/food input of your system, and testing for the ions and their rates of depletion. Also, sandbed area has to be large enough to be able to completely utilize nitrogenous nutrients in order to maintain oligotrophic (nutrient poor) conditions. It should also go without saying that high energies above the sandbed and light resonant of levels found on natural reefs are integral (of course, "resonant" referring to "as close as possible by a hobbyist/aquarist").


Ok thiers a start.


MIke

[NaH2O]

That is great, Mike. I just need to digest it and think about it for a minute...I'll be tagging along....

[swissgaurd]

Mike
you hit the jaubert system .right on the nail.
I ran a 55 gallon system for approx. 5yrs with the plenum.fish looked good.corals seemed to love it.water parameters were always good exept i had a cyno outbreak once,but it did not last long.it was quite simple to set up the system.i had a one inch plenum space below the substrate.my first layer was crushed oyster shells,which was chicken feed,this prevented fine sand from escaping below the eggcrate.crushed oyster shell thickness was approx. 1 inch deep.On top of the oyster shells i put 2 inches of a sugar grain sand and mixed in 2 pounds of live sand.I also set up 2 other systems wich are still in operation one system is a 65 gallon using crushed coral instead of the oyster shells and uses a protien skimmer he has now installed a refugium.the other system is a 75 gallon system and has no protien skimmer the tank has been highly neglected for 1 yr tank got a hair algae problem and is finally getting back on track,cause i started *****in
of the amount of work and money that was spent.tank should look aussum by christmas.this tank also uses crushed coral.also has purchased a skimmer for tank.
I really dont see any draw backs to the jaubert system except it is designed to run without a skimmer but i do believe that you should use one.also a jabert plenum takes away alot of headspace from the tank.my first success story was with a plenum system.

vic

[ScottT1980]

First-off, well done mojo/poo/Mike

Also called the Monaco-style system becausze of its use (and success) in the Monaco aquarium.

Here is a link to more specific information about the Monaco system

This is similar to the system I run in my tank and it seems to be just as effective as a DSB, although I question whether it is more effective. I think substrate size is crucial and I don't have that nailed down at this point. FWIW, I also run with a skimmer and a fuge so it is incorrect for me to say that I run a Jaubert or a Monaco system, just that I have a plenum.

Anyway, I forgot what else I was going to say so good work Mike!

Take er easy
Scott T.

[Scooterman]

http://www.wetwebmedia.com/PlenumFAQs.htm

http://www.wetwebmedia.com/deepsandbeds.htm

I thought some of you may want a good read, on top is great details ond DSB's also.

[jks1]

More great info Mike, thanks

[Maxx]

One thing to keep in mind w/ Jaubert/ Monaco/ Plenum systems....little rockwork, and light bioload, are required in order to provide a LARGE (reletive to the tank's footprint) surface area. The rock will compract the substrate and reduce the effectiveness of the plenum, otherwise. Juabert also had typically light biloads in order to keep from overwhelming his set up w/ detritus.
Nick

[mojoreef]

Maxx very strong points. so lets take that a bit further. on the bioload it would seem that the massive water change scheme would work to help, but that may be tough for us, would occational syphoning of the bed maybe even out the inputs to outputs??
On the substriaght compression, this is a problem both dsb and plenums have, would remote locations be more effective.


mike

[ScottT1980]

On the substriaght compression, this is a problem both dsb and plenums have, would remote locations be more effective.

Everything that I have read suggests that this would be the optimal choice. In fact, much of the literature suggests that a remote plenum is perhaps better than a remote DSB (not to get into the debate, just what I remember reading).

I have a question as well, I was told that a plenum allots for a good bit of Calcium release into the water column (compared to a DSB) through the breakdown of aragonite. Has anyone found this to be the case? I certainly have not with my system...

Take er easy
Scott T.

[mojoreef]

Scott the one thing that I think makes a strong arguement for this system is the particle size and the high flow energy used. the lower Ph in oth the dsb and the plenum will allow for the melting of argonite (also bacterial acids play a strong role). with a larger particle sizes migration of elements would seem to be better. In relating that to his setup I would say the constant water changing keeps his levels at the normal ocean concintration and then the small amounts of of carbonate and calcium from the plenum wold bump it a bit. I dont think this would apply to what we are trying to do in our tanks, but we could say that if we can maintain our levels with an outside source (calreactor/ kalk/additves) it would help in the process.

mike

[Maxx]

So now we're discussing the possibility of remote plenums....I like the idea, can see some merits. But what size plenum are we talking about? Do I need a 65 gallon plenum set up to be effective on my 58 gallon tank? Also, if I understand you correctly, you're saying that vacuuming plenums is okay, and should be done? If this is the case why have we not seen a large sweeping remote plenum movement? Or are you guys so cutting edge that I can claim I saw it here first????
genuinely curious here,
Nick

[swissgaurd]

I tried vacumuming and stirring the sand bed this caused a few algae problems the best method i found was just let it be and use the use of nassurios snails to maintain the sand bed.
I do find it was easier to maintain calcium levels though.

vic

[NaH2O]

Originally posted by Maxx
So now we're discussing the possibility of remote plenums....I like the idea, can see some merits. But what size plenum are we talking about? Do I need a 65 gallon plenum set up to be effective on my 58 gallon tank?

Interesting point, Nick. A remote plenum to be effective may have to be quite large to gain any benefits, and may be more of a hassle than to have one in the main system.

[mojoreef]

Well Nick we are breaking it down. On the question of remote or not, thats what this is all about. OK here is the breakdown as I see it so far. Plenumn system outline as it it in a public aquarium with lots of flow and constant waterchanges, for me taking this sytem as it is in monaco and dumping it into a reef tank is going to be hard to do and it needs some mods to make it work for a hobbist. So first thing to do is to recognize the problems (maxx's first one, compressed substraight), so lets figure out how to get past it, first responce, go remote, so next is are thier problems with that or are thier alturnative methods around it??
By the time we get through we got a fully explained system..that works

Mike

[Maxx]

I love it when you run w/ these structured discussions Mike! I know you already got the answer, but ya stil gotta make us work for it! All right, I'm up for the pepsi challenge....
For plenums to work, they require time to convert the nitrates into non harmful compounds. They also require surface area to do this. So the major rationale of not running a remote plenum is the space requirement involved....
hows that for starters?
Nick