Sulphur Denitrators - 18 years and Counting

[Gouldian]

A recent post in Pasar Malam re-kindled my interest in Sulpur Denitrator.

Professor Guy Martin from Ecole Nationale Supérieure de Rennes was believed to be the first person to applied the sulphur denitrification into freshwater treatment for public. In 1991, Marc Langouet, who is a student of Prof. Martin decides to test this method on seawater. After 3 years of testing without apparent toxicity, Marc proposed the idea to Michel Hignette - Curator of MAAO Paris. And the rest, as most will say, "Its History".

I have a Korallin C1502 Calcium Reactor which I have converted to Sulphur Denitrator 2 years ago but disconnected after I kept Nitrate in check. However, as I added more fishes Nitrate began creeping up to about 4-5ppm. As I currently do not run any other Nitrate Reactor or Bio-Pellets Reactor, I decided to do a simple experiment before I install into my main tank.

In Sulphur De-nitrifications, Thiobacillus denitrificans and Thiomicrospira denitrificans, are able to use reduced sulfur compounds as electron donors and respire on nitrate in the absence of oxygen. What it means in layman terms is that the bacteria will strip Oxygen from Nitrate and by-product will be Nitrogen.

According to Randy Holmes-Farley, herewith is the equation - 2 H₂O + 5 S + 6 NO₃^- → 3 N₂ + 5 SO₄^2- + 4 H^+.

Korallin Sulphur Denitrator, this reactor has be disconnected from my main tank 2 years ago, as you can see the media (Sulphur & Carbonate) has turn black in certain parts.

Water container A and B. Both container will contains similar amount of water from my current tank.

DD Test kit, in my opinion this is by far one of the best I have used. It allows you to both test for NO3 and NNO3.

Nitrate Test on Container A = +-4ppm

Nitrate Test on Container B = +-4ppm

Container A will be connected to the Sulphur De-nitrator while Container B will be Control.

Container A and B in position

Both container will remain in the semi-darken sump area of my tank for 1 week. No additional intervention.

.... Day 7 ....

Water from Container A of the left and water from Container B on the right. Notice water from A is brownish due to dirty Reactor. This picture is taken before adding reagent.

Side by side comparison of water from A and B. A with Sulphur de-nitrification read 0 while B is 0.50 on the low range test of DD test kit.

Pros:

• Short kick-in time compared to carbon based de-nitrator
  
• No hassle of constant feeding of ethanol
  
• Efficient even for Nitrate below 5ppm
  
• No need for additional feed pump (Applicable for Korallin and similar designed reactors)
  
  Cons:
  • Prolonged used may lower pH
    

  FAQ extracted from - http://reefkeeping.c...1/diy/index.php

  How long does the media last? About 3 years according to the manufacturer.

  Is it hard to adjust? Not harder than a calcium reactor. The only daily adjustment you have to make is to degass the system from the top valve. About 5 seconds.

  What is the effluent's pH? The pH out of the effluent in my unit reads 7.5

  I smell rotten eggs out of the effluent? The bacteria are not getting enough food (nitrates). At this point the unit needs higher flow or some of the media needs to be removed.

  Can I store the media for later use? Yes, wash the media thoroughly with RO/DI water and store in a sealed container for future use.

  Do I have to use aragonite on top of the sulfur media? No, but it helps to buffer the pH a bit and it buffers your tank at the same time. Don’t count on this to replace your calcium supplement anytime soon.

  Do I still need to do those dreadful water changes? Yes, water changes help dilute some of the more toxic compounds in your water and replace all the lost and absorbed trace elements in your aquarium.

  Do I need a recirculation pump? Yes, all figures are based on this. Recirculating reactors are much more efficient and are better at preventing media channeling. It also prevents air pockets within the media that kills the anaerobic bacteria which we're trying to culture.

  Can I use a bigger recirculation pump? Yes, you will have to throttle it back with a valve to prevent the media from fluidizing and becoming mush in there.

  Does Hydrogen Sulfide accumulate when using one of these denitrators? In most cases, no harmful concentrations of H2S will occur. If you are overly concerned about this there are two way to combat it:

  (1) Maximize aeration. A high oxygen level drives hydrogen sulfide oxidation, and high aeration will drive some off as volatile H2S gas.

  (2) Pass the water over iron oxide/hydroxide (GFO) to convert hydrogen sulfide to elemental sulfur.

  What are the cons of running a sulfur reactor? Your Alkalinity levels will drop faster than without using a sulfur reactor. It is imperative that you keep an eye on this parameter.

  So will I be adding this reactor to my reef tank? Yes for the time being as I am experiencing higher nitrate than I normally used to. However, I will dis-connect and reconfigure into a Calcium Reactor once I am done and have the CR run permanently when I am tired on dosing 2 parts solution plus magnesium.

  Happy Reefing.

  Ref:

  http://www.aquarium-...seascope_gb.pdf

  http://reefkeeping.c...1/diy/index.php

  http://www.advanceda...003/8/chemistry

  http://en.wikipedia.org/wiki/Mus%C3%A9e_national_des_Arts_d'Afrique_et_d'Oc%C3%A9anie

  http://mars.reefkeep...atorSoufre.html

  http://mars.reefkeep...rDenitrator.htm

  This post has been promoted to an article

[peacemaker]

:thumbsup:

[nanos]

Nice read.

[shootsimon]

salute you bro

[QwekSengKiang]

Great innovation and sharing.

[sharonleong]

So in short you reduce nitrate by using  Sulphur Denitrator? Can it be use on any kind of reactor?

 

So will I be adding this reactor to my reef tank? Yes for the time being as I am experiencing higher nitrate than I normally used to. However, I will dis-connect and reconfigure into a Calcium Reactor once I am done and have the CR run permanently when I am tired on dosing 2 parts solution plus magnesium.

 

If you discontinue using it wont the nitrate increases again? What is 2 part solution?

[tofubox]

When people ask about best way to remove nitrate or phosphates, the more important / appropriate question is "whats the most economical way to remove phos/nitrate"? 

There are tons and tons of methods of removal, Macroalgae, Absorption media (so many brands), Water change, Biological media, ULNS, Algae scrubbers, Tons of bacteria housing, AIO Bio-pallets etc etc. 

It depends A. Your tank size, B. Your Bioload C. Your feeding regime 

Simply put, for a small tank in the past, I chose to use Algone pouches, just dump it in the filter and left it till it needs replacement. I also had a small TLF reactor running rowaphos fed from the chiller output. This was really economical for a small size tank. The pouch could last 1.5 months, the rowaphos every mth change few scoops of media. 

But moving to a bigger 4ft tank, this was no longer an economical method as too many pouches will be required. 

Choose the most economical method. All of the methods work, its just how much of it you need to use. I.e 5 pouch of Algone? A 2 ft macroalgae tank? 1 container of Rowaphos every mth? 3 sets of Algae scrubber? 2 bags worth of zeovit / zeolight stones / Bio-pallets? or simply, 1 Sulphur denitrator that is an overkill for ur tank size?

As to your questions Sharon, reefing has evolved alot over the years, look at some of the alternative methods which are more efficient and effective. A sulphur denitrator works similarly, but it needs more understanding to use safely. The best thing to do if you are facing high nitrates atm is to clean up the system, followed by a water change, than maintain a more healthy feeding / stocking regime. Hope this helps.

 

[sharonleong]

On 21/07/2016 at 11:39 PM, tofubox said:

When people ask about best way to remove nitrate or phosphates, the more important / appropriate question is "whats the most economical way to remove phos/nitrate"? 

There are tons and tons of methods of removal, Macroalgae, Absorption media (so many brands), Water change, Biological media, ULNS, Algae scrubbers, Tons of bacteria housing, AIO Bio-pallets etc etc. 

It depends A. Your tank size, B. Your Bioload C. Your feeding regime 

Simply put, for a small tank in the past, I chose to use Algone pouches, just dump it in the filter and left it till it needs replacement. I also had a small TLF reactor running rowaphos fed from the chiller output. This was really economical for a small size tank. The pouch could last 1.5 months, the rowaphos every mth change few scoops of media. 

But moving to a bigger 4ft tank, this was no longer an economical method as too many pouches will be required. 

Choose the most economical method. All of the methods work, its just how much of it you need to use. I.e 5 pouch of Algone? A 2 ft macroalgae tank? 1 container of Rowaphos every mth? 3 sets of Algae scrubber? 2 bags worth of zeovit / zeolight stones / Bio-pallets? or simply, 1 Sulphur denitrator that is an overkill for ur tank size?

As to your questions Sharon, reefing has evolved alot over the years, look at some of the alternative methods which are more efficient and effective. A sulphur denitrator works similarly, but it needs more understanding to use safely. The best thing to do if you are facing high nitrates atm is to clean up the system, followed by a water change, than maintain a more healthy feeding / stocking regime. Hope this helps.

 

One container of rowaphos that not very cost effective.

Do we really need one bag of bio pellets per month?

Can share which regime you take to keep nitrate at 0ppm?

[sherman]

If you can spare time  dose carbon will bring NO3 under control.

You going for ulns? Zero is no good for both PO4 and NO3 unless you doing ulns

[Belgian Anthias]

Using sulfur in biofilters is very effective. When SPC ( BADES- columns) are used a reactor is not needed. Simultane nitrification and mixotrophic denitrification.  Nitrate is instantly removed the moment it is produced. BADES-columns are roles of elemental sulfur mixed with calcium carbonate source ( oyster shell grit?)

http://www.baharini.eu/baharini/doku.php?id=en:badess:start

Most sufur denitrators are used as they were carbon driven denitrators and are kept anoxic by limiting the flow. Sulfur denitrators  are not managed the same way . Sulfur denitrators ( used in MAAO) are not kept anoxic. BADES-reactors have a flow of at least +- 1x the total volume of the system each day. BADES bio-reactors  and BADES-denitrators are NOT kept anoxic!

Something to read about BADES ( Biological Anaerobe Denitrification on Elemental Sulfur) and BADESSystems: http://www.baharini.eu/baharini/doku.php?id=en:badess:theorie:start

 

[Belgian Anthias]

Using sulfur in biofilters is very effective. When SPC ( BADES- columns) are used a reactor is not needed. Simultane nitrification and mixotrophic denitrification.  Nitrate is instantly removed the moment it is produced. BADES-columns are roles of elemental sulfur mixed with calcium carbonate source ( oyster shell grit?)

http://www.baharini.eu/baharini/doku.php?id=en:badess:start

 Sulfur denitrators are  often used as they were carbon driven denitrators and are kept anoxic by limiting the flow. These denitrators have a very low potential when a lot of nitrate has to be removed wile keeping a very low nitrate level.

BADES- denitrators  are not managed the same way . Sulfur denitrators as used in MAAO are not kept anoxic. BADES-reactors have a flow of at least +- 1x the total volume of the system each day. BADES bio-reactors  and BADES-denitrators are NOT kept anoxic!

Something to read about BADES ( Biological Anaerobe Denitrification on Elemental Sulfur) and BADESSystems: http://www.baharini.eu/baharini/doku.php?id=en:badess:theorie:start