Sulfer beads and denitrification

[Herbert T. Kornfeld]

How much are we talking here...???

[Uel]

Over 300.00 locally.

[hex1]

An ORP meter is really a millivolt meter, measuring the voltage across a circuit formed by a reference electrode constructed of silver wire (in effect, the negative pole of the circuit), and a measuring electrode constructed of a platinum band (the positive pole),
all you would need is a couple of bnc connectors and some cable to reverse the polarity of the probe wires,ie make a crossover cable, the display will now read backwards ie negative orp will be displayed as positive, and the controlling circuits should function the same as if you were using ozone.

[Herbert T. Kornfeld]

got a diagram? In in EE, but you still got me without more details.

[hex1]

sorry no diagram yet, they are just little voices in my head right now
I have the pin point orp controller it is capable of reading in the range of –1,999 to +1,999 mV
this controller will activate the 110 output switches only within the positive range of ORP. +1 to +1,000 mV

because this is just a volt meter, if you reverse the polarity of the probe inputs ie: neg wire on probe connected to pos terminal on the meter and vice versa, a -300 orp fed in "backwards" should display as a +300 ,

this controller has two AC outlets, one of these can be energized when the ORP is above the setpoint.

havent sorted out how to control the flow just yet but i am thinking of setting up the minimal flow via just gravity feed with a airline.

a small pump connected to the controller will add additional flow via a second input if the orp goes above ~ - 275 meaning i am about to make hydrogen sulfide and need a little more oxygenated water

My sulfur and calcium media are on the way so i have a few days to sort the rest of this out.

[Whaledriver]

Can you just bury the beads in a deep sandbed? If they are on the bottom of a 4-6 inch bed would they boost the productivity of a DSB?

[Roadtoad]

I read that some people were using sulfur in their plenums so I dont see why it wouldnt work in a DSB. I was thinking that it might work in a calcium reactor too

[Uel]

Interesting idea RT. I just think you would run into problems with which effluent to base your drip on. What would the effect of the co2 be on the sulfur?

[Roadtoad]

The denitrifying bacteria that live in marine substrates and use sulfur appear to be able to operate in low pH conditions. I dont think the CO2 will be a problem, they just need to have anoxic conditions. I was thinking of putting the sulfur in the second chamber to have the bacteria in the first chamber get rid of any oxygen from the water feed. You are right though, the effluent monitoring would have to require pH, Alk and ORP of the outflow.

Does anyone know if monitoring nitrite is as effective as ORP?

[Herbert T. Kornfeld]

Sulpher reactions arent able to operate in low pH conditions, they generate the low pH conditions. I wouldnt do it, unless you covered the sulpher layer with some crushed seashell to buffer the pH...as regular arag sand wont...and you would have pH problems. It is very important to have the seashell layer.

At that, the sulphur reactor and crushed shells need to be replaced from time to time, so you would have to dig up your sand from time to time to replace the shells which dissolve pretty quickly (into a mush).

This transition would also change the flow through the bed.

The sulphur also needs to be monitored frequently to make sure that its well controlled flow is just right...or else worse things happen. This control and monitoring would be impossible if the media were in a sand bed.

[jordan2871]

Whats the difference between using a sulfur reactor and feeding your tank more food ie. Nitrogen cycle??

I have thought about adding one but always harken back to the natural cycle. We do have closed systems and hence eventually have to make a water change to dilute the pollutants that build up.

[Herbert T. Kornfeld]

But a sulpher reactor eats nitrates...feeding the tank more makes more nitrates (and phosphates). The sulpher reactor isnt to add nitrates...it eats them.

[reefclown]

Sulpher reactions arent able to operate in low pH conditions, they generate the low pH conditions. I wouldnt do it, unless you covered the sulpher layer with some crushed seashell to buffer the pH...as regular arag sand wont...and you would have pH problems. It is very important to have the seashell layer.

not so sure

take a look at these and let me know your thoughts

http://aem.asm.org/cgi/content/full/64/1/119

The pH range is from 6.0 to 8.2 with an optimum of 6.7 to 7.3

http://www.pubmedcentral.nih.gov/pic...6&blobtype=pdf

In the first such culture, apH value of 6.9 was maintained, and subsequent cultures

Additionally this recent patent specifically seperates out the processes

http://www.freshpatents.com/Autotrof...pe=description

[Roadtoad]

Nice lit search reefclown! I didnt even think of searching pubmed.

The first paper you have listed shows that the species of bacteria grow in an appropriate pH range (6.0 to 8.0) so a calcium reactor should be fine. Unfortunately they found that the bacteria would not use nitrate as an electron acceptor which would indicate that it does not denitrify.

The species of bacteria from the second paper does denitrify and they show good denitrification using thiosulfate as a substrate at pH6.7. They mention that it works at 6.0 in the presence of CO2 in the discussion. So at least with this particular bacterium, dentrification will work at low pH and with CO2.

I didnt read the papers entirely so I might be wrong, there is just something about scientific papers that makes me sleepy.

I guess that I missed my window on the patent by a couple of years! I am surprised that they could get a patent on something that was relatively common knowledge on the web prior to their submission date. Maybe they made a significant improvement, I will have to see.

I should have my calcium/sulfur reactor running this week, we will see how it goes. Basically all I did is put 5lbs of sulfur in the second chamber of my diy reactor then put reactor media on top of it.

[Herbert T. Kornfeld]

Let me rephrase that...what I meant to indicate was that the bacterial process that the supher enables is the reason for the pH drop. What you seemed to indicate was that the sulpher reactor needed the pH lowered to operate or something...which it does not. The cause and effect were mixed up. Of course sulpher can work in lower pH environments...but it doesnt need help...it does this on its own. The addition of CO2 is not needed, and I think would actually work against you....as the process eats nitrates and produces CO2, so adding more CO2 would end up simply lowering the pH and melting more crushed shells, not aidint bacteria. The reaction of the bacteria with the sulpher media eats nitrates and produces CO2...adding CO2 would be like adding Oxygen to a plant tank.

Also, placing sulpher in a low pH environment would be the same. I think some here are getting their cause & effect mixed up here. The sulpher & bacteria reacton produces the lower pH...lowering the pH isnt going to help the ingoing balance of chemicals or boost production. Once again, its like dosing oxygen to a plant tank. The pH and CO2 are byproducts of the sulpher reactor, not ingoing, nor performance enhancing variables.

Thinking that lowering the pH or adding CO2 will help your sulpher reactor is like a logic which would say "since your car makes exhaust as part of its engine's chemical reaction, it must like exhaust, and feeding the engine more exhaust would somehow boost its performance".

Do you get the logic flaw here? Lowering the pH or adding CO2 would only result in more of the calcium substrate (crushed shells) dissolving and turning into mush. But this would also impede the sulpher reactor's production because if you saturate the water with CO2, and a lower pH, the bacteria will not be able to release their CO2 and pH lowering chemicals any more because the water is already saturated. Much like adding exhaust to a car engine would result in its eventual decline in performance until the point where it would no longer be able to combust.

[reefclown]

Hi Herb,
All I am saying is that I do not believe that the statement you provided is correct.

Sulpher reactions arent able to operate in low pH conditions, they generate the low pH conditions. I wouldnt do it, unless you covered the sulpher layer with some crushed seashell to buffer the pH...as regular arag sand wont...and you would have pH problems. It is very important to have the seashell layer.

AFAIK.

1. Suplhur reactions ARE able to operate in a low ph environment.

2. It is NOT very important to have the seashell layer.

The response re C02 e.t.c, I'm still trying to figure out where all that came from

Adding calcium carbonate/aragonite media to the denitrator directly has the risk of creating a mush (just like with a ca reactor), I still feel it is easier to control the process if the sulphur and calcium chambers are kept seperate, the sulfur output simply feeding into the calcium input. As to which of these methods is the more effective, I have as yet no idea. The manufacturers seem to have taken the combined approach though, I'd like to see the benefits over and above seperate chambers.

I started a post a while back in order to get a view of what bacterial/chemical processes people think are occuring within the denitrator, as it all still seems a rather black art, with no single manufacturer providing any indepth information AFAIK. Would be nice if we could nail the process down a little further

http://archive.reefcentral.com/forum...hreadid=679806

As I'm not a chemist or biologist its proving a long but interesting learning curve researching this area to find what should be well documented processes.

Does ANYONE know the bacterial strains that are responsible?

I guess that I missed my window on the patent by a couple of years! I am surprised that they could get a patent on something that was relatively common knowledge on the web prior to their submission date. Maybe they made a significant improvement, I will have to see.

Trying to patent a process that is probably 10-20 years old I find simply stunning, If seriously doubt if the patent will get approved in it's current format.

A pre-chamber to kill of the oxygen is a nice addition.

[Roadtoad]

HTK-
Here is my logic
1. The bacterial processes involved in denitrification are not inbited by high CO2/low pH.
2. They require anoxic environments where the bacteria can reduce nitrate and transfer the oxygens to make sulfates/sulfides
3. There are two ways to go, build a stand alone sulfur reactor or attach it to a calcium reactor. In my particular case the easiest way to have a controlled flow-low O2- environment is to place the sulfur in the second chamber of my calcium reactor. Water will flow through the first chamber and be depleted of oxygen (it will also be acidified and calcium loaded). Next the water will enter the second chamber where it will be stripped of nitrate, further acidified, then flow into reactor media that will buffer the pH and add a little more calcium/carbonate. it will then leave the reactor and enter the remainder of the system. The effluent should be the same pH with or without the sulfur, due to the carbonate buffer. the only difference is the absence of nitrate.

If the bacteria dont care and can work in a given environment I dont care if they make the water acidic, it will get buffered out just like the CO2 from the reactor. We will see soon.

[Herbert T. Kornfeld]

Roadtoad,

http://www.marinedepot.com/aquarium_...or.asp?CartId=

Of course a reactor would work well...just dont feed it CO2, its pH will drop enough on its own. I understand that sulpher reactors can work in a low pH environment (to a point of course)...they have to deal with their own output of course. I just wanted to clarify that lowering pH, providing the reactor with low oxygen, or dosing CO2 (all part of the same cause & effect here), are not needed for a sulphur reactor. I am unsure as to if it would have any benefit or impact on the ability for the bacteria to eat nitrates, but it might (logic is that too much of what the bacteria are trying to get rid/ouput of would impede their intake).

It was comments like jordan's above that urged me to make the clarification, as adding more food does not equal a nitrate reactor (he must have thought that a nitrate reactor was to make nitrates, lol!).

C:\Documents and Settings\Jon\Desktop\7 Reef\Remove nitrates from your fish tank.htm

the whole idea of a sulphur based reactor was to eliminate the need to dose CO2 or bacteria food. The sulphur is all they need.

C:\Documents and Settings\Jon\Desktop\7 Reef\Reefs_org Bulletin Board View topic - Sulphur Reactor Denitrification.htm

http://archive.reefcentral.com/forum...538359#newpost

C:\Documents and Settings\Jon\Desktop\7 Reef\La dÈnitratation sur Soufre en pratique.htm

The above is a good collection of sulpher denitrator info, with randy holmes-farley even adding in.

And the bacteria in question isThiobacillus denitrificans.

[reefclown]

And the bacteria in question isThiobacillus denitrificans.

thanks, pretty much what the patent states and the second paper confirms.

ooh. your links point to your local drive so are not viewable.

[Herbert T. Kornfeld]

Oh, I so stupid...I knew I was doing that and I still did it anyways...

here...
http://www.aquaticeco.com/index.cfm/.../4912/cid/1387

http://www.reefs.org/phpBB2/viewtopi...=896634#896634

http://mars.reefkeepers.net/USHomePa...ionSoufre.html


The above are in the same order as the ones missing above.

[Roadtoad]

if you look at the stoichiometry of the reaction, denitrification with sulfur really stinks as a method of powering a calcium reactor. There isnt enough acid made to dissolve much. There was a post regarding this in the chemistry forum a while back.

[reefclown]

HTK,
will all respect the links don't provide anything other than a method/product without any indepth information on how the process works chemically/biologically.

There are a number of competing bacterial organisms that could fullfill the same role, what I'm seeking is some concrete evidence of what occurs inside the reactor. I accept that in all probability that which has been stated is possibly correct.

if you look at the stoichiometry of the reaction, denitrification with sulfur really stinks as a method of powering a calcium reactor. There isnt enough acid made to dissolve much. There was a post regarding this in the chemistry forum a while back.

I don't think the purpose is to power a calcium reactor, simply to reduce nitrates, AFAIK the use of calcium carb/arag is simply to neutralise the acid prior to returning to the system.

The addition of calcium
skewing of alkalinity
increase in suplhate
potential reduction of tertiary electron acceptors (Fe, Mn e.tc)
potential production on hyrdrogen sulphide
are just a side effects ?

[Herbert T. Kornfeld]

http://www.engg.ksu.edu/HSRC/97Proce...mediation.html

As you can see, lowering the pH too much would result in decreased effeciency of the reactor...so adding sulphur to a dsb, or dosing it with CO2 or water that is more acidic is much like trying to run your car off of exhaust. All the hydrogen that gets released from the process has a maximum saturation level in the water (shown in lowered pH), and once ot goes too low the bacteria stop working. So to feed one off of a calcium reactor (or putting it in a DSB) would not be the best idea, Roadtoad. Run them seperately. Feeding it fresh water is the way to go, and it will lower the pH in the system by itself. If anything, you would want to raise the alkalinity of the reactor...not dose it with CO2 and lower it.

Is this the evidence you were looking for? I thought it was pretty self evident...but if you need proof...

And BTW, the process works the same in saltwater as in fresh, only not quite as fast.

[barryhc]

So, a fission reactor does not operate by "feeding the control rods".

Municipal water systems use fluctuations between aerobic and anaerobic bacteria to accomplish these functions. I understand that you are discussing calcium and pH VS acidic and denitrification functions here, but if you try to incorporate too many of these funstions within a single filter, or piece of technology, you will sacrifice some portion of the intended function for "another".

> barryhc

[d-town tony]

I think you guys are making running this reactor a little more complicated than need be. I don't even test anymore.

I set up my H & S in late winter last year, set it then and haven't adjusted it again.

I have 21 fish in my 175gal, a couple big ones and a lot of little ones.
I'm running barebottom. All the DSB guys said their DSB cut their nitrate, so at the time I ordered it I figured, heck the best of both worlds.

Thing works great, haven't unplugged it since I put it in. Wish I would have had one of these 5 years ago in my fish only tanks.

If you have high nitrates, be careful, these things will knock your nitrates out so quick you will shock the tank.

pH/flow/everything else are not that great of a worry unless your nitrate production is off the chart

I started looking at these over a year ago and people were telling me I was nuts, wasting money, etc. I put one in and noticed changes of color/growth/fish within a couple weeks.

JMO/JME
tony