DIY Sulfur Denitrator
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Belgian Anthias
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There should not be any rotten egg smell. I have no experience with mixed systems but in a sulfur-denitrator this is only possible in a clogged filter which provokes channeling of the effluent true the media.
1 drop per 3 seconds will clean 1 ml in 1 minute. This means this filter will clean 60ml in 1 hour or 1,44 liter per day. A sulfur-denitrator should be measured that the system water can pass the filter once or twice a day!
denitrator
denitrator
Sorry to wavier of the topic slightly but i had a question regarding the sulphur media.
I picked up a used korallin denitrator a couple of months ago and after running i still am not getting a reduction in my nitrates ,so i figured the media maybe old researching on line i came across sulphur prills 99% pure sulphue used for gardening purposes also to to increase the acidity of water used in sprinklers .
Do you think this would be okay to use in my denitrator?
Compared in price it is about a 75% less then the Korallin replacement media.
denitrator
Sorry to wavier of the topic slightly but i had a question regarding the sulphur media.
I picked up a used korallin denitrator a couple of months ago and after running i still am not getting a reduction in my nitrates ,so i figured the media maybe old researching on line i came across sulphur prills 99% pure sulphue used for gardening purposes also to to increase the acidity of water used in sprinklers .
Do you think this would be okay to use in my denitrator?
Compared in price it is about a 75% less then the Korallin replacement media.
Belgian Anthias
New member
Sulphur for gardening purposes ( in burners) may contain chemical additives to slow down the burning process. Make sure there are no chemical additives.
The use of pure sulphur prills for gardening purposes should be no problem.
Belgian Anthias
New member
What you have heard is not correct. In a sulphur de-nitrator the bactaria do not need nitrate to survive. the cultivated bacteria can use the sulphur as a power source. That is why we use sulphur! It is importend NOT to ad a carbon source media to a sulphur de-nitrator as some specialists may advise because the cultivated bactaria can not survive on sulphur! A sulphur de-nitrator should be used continiously. The system water should pass the reactor once or twice a day!
The reaction from the sulfur reducing bacteria includes the use of alot of nitrate,which is why is why it's used and called a sulfur denitrator.
The reaction :
H20(water) + S(elemental sulfur) + CO2(carbon dioxide)+NO3( nitrate) ------->N2 (nitrogen gas) + SO4( sulfate )+H (hydrogen) + organics (C5H7O2).
When the nitrate runs out and the water becomes anoxic ( no oxygen/ no nitrate) sulfate reducing bacteria using the sulfate for oxygen instead of nitrate take over and hydrogen sulfide ( sewer gas ) production follows.
So, if the amount nitrate entering the reactor via flow through from the tank water doesn't match the amount of sulfur in use ; toxic odoriferous H2S /sewer sewer gas becomes a problem. This happens often as the nitrate in the tank water is depleted. The idea is to get the reactor to reduce nitrate equal to the amount input via foods, etc on an ongoing basis. It's difficult to tune that balance in in many cases.
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The reaction :
H20(water) + S(elemental sulfur) + CO2(carbon dioxide)+NO3( nitrate) ------->N2 (nitrogen gas) + SO4( sulfate )+H (hydrogen) + organics (C5H7O2).
When the nitrate runs out and the water becomes anoxic ( no oxygen/ no nitrate) sulfate reducing bacteria using the sulfate for oxygen instead of nitrate take over and hydrogen sulfide ( sewer gas ) production follows.
So, if the amount nitrate entering the reactor via flow through from the tank water doesn't match the amount of sulfur in use ; toxic odoriferous H2S /sewer sewer gas becomes a problem. This happens often as the nitrate in the tank water is depleted. The idea is to get the reactor to reduce nitrate equal to the amount input via foods, etc on an ongoing basis. It's difficult to tune that balance in in many cases.
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Belgian Anthias
New member
The other way arround.
The other way arround.
Your explanation is not correct for a sulfhur de-nitrator. This reaction will only happen in a clogged reactor. Aqua water will alway's contain some nitrate and the use of a fluidized reactor prevents clogging. The system water must pass the reactor once or twice a day, so the amount of sulphur must match with the amount of water in the system and NOT with the amount of nitrate in the system. The bactaria can use the sulphuir as a power source, that's why we use sulphur and not a carbon containing media.
Please read this:http://filebox.vt.edu/users/chagedor/biol_4684/Cycles/Soxidat.html
A sulphur reactor can be closed for one month and reused immediately. When started up again the first water must be wasted an d a rotten egg smell is noticeable for a short time. Incubation time will be only a few day's. This means the bacteria survive. Most of the reactors are to small for the system and not enough sulphur is used. A sulphur reactor works completely different compared with a carbon based reactor and is a lot more reliable and easy to manage. Once working, you can leave it for a year, if you want to, it will still work fine.
Thiobacillus denitrificans, can and will oxidise sulfide to harmless sulfate, using the freed oxygen.
The other way arround.
Your explanation is not correct for a sulfhur de-nitrator. This reaction will only happen in a clogged reactor. Aqua water will alway's contain some nitrate and the use of a fluidized reactor prevents clogging. The system water must pass the reactor once or twice a day, so the amount of sulphur must match with the amount of water in the system and NOT with the amount of nitrate in the system. The bactaria can use the sulphuir as a power source, that's why we use sulphur and not a carbon containing media.
Please read this:http://filebox.vt.edu/users/chagedor/biol_4684/Cycles/Soxidat.html
A sulphur reactor can be closed for one month and reused immediately. When started up again the first water must be wasted an d a rotten egg smell is noticeable for a short time. Incubation time will be only a few day's. This means the bacteria survive. Most of the reactors are to small for the system and not enough sulphur is used. A sulphur reactor works completely different compared with a carbon based reactor and is a lot more reliable and easy to manage. Once working, you can leave it for a year, if you want to, it will still work fine.
Thiobacillus denitrificans, can and will oxidise sulfide to harmless sulfate, using the freed oxygen.
Your explanation is not correct for a sulfhur de-nitrator.
I disagree. While I think sulfur denitrators are useful and manageable with effort, I think your conclusions about what's going on are off.
Aqua water will alway's contain some nitrate
Nitrogen deficiencies often occur in aquariums. Such a deficiency is likely with a lot of nitrate reduction to dintrate( N2 gas) which can outpace nitrogen inputs form foods,etc. The amount of nitrate reduction does relate to the amount of sulfur being oxidized which relates to the amount of nitrate or free oxygen available .
I don't know why you identified Thiobacillus dentrificans as the main or sole player in a sulfur denitrator; it may be so. It's worth noting ,however,there are many species of bacteria and many sulfur bacteria some of which are used for hydrogen sulfide production for commercial purposes. Nevertheless, since you noted it , let's take a look at Thiobacillus nitrificans and how it acts in a denitrator .
Thiobacillus nitrifcans is a chemolithoautotrophic bacteria. It gets energy from oxidizing an inorganic compound(sulfur).Thus, it doesn't need organic carbon for energy like heterotrophic or photoautotrophic bacteria do.
It needs oxygen in order to oxidize the sulfur.
It is facultative;able to use free oxygen and when it's exhausted nitrate(NO3) for oxygen. When the water becomes anoxic (no oxygen and no nitrate) it can't oxidize the sulfur and can't get the energy it needs to thrive. This sets the stage for sulfur reducing bacterial activty which reduces sulfate(SO4) with toxic hydrogen hydrogen sulfide as a by product.
Thiobacillus denitrificans also needs to uptake some nitrogen via assimilation in order to grow and won't thrive without it. This is from the paper you cited:
(T.denitrificans) can also carry out anaerobic respiration, using nitrate as the terminal electron acceptor, while oxidizing the elemental sulfur to sulfate. However, they lack the ability to synthesize assimilatory nitrate and nitrite reductases, therefore a source of ammonia/nitrogen must be present for cell/protein synthesis to take place.
It also needs some carbon for it's biomass and gets it by fixing CO2 as noted in my previous post.
I think when you just turn up the flow these bacteria will thrive on the oxygen in the water and keep on oxidizing sulfur that way if there is at least enough nitrogen for them to grow. Of course just oxidizing the sulfur to sulfate without nitrate reduciton serves no benefit and can throw the sulfate ;chloride ratios in the tank out of balance over time.
Thiobacillus denitrificans, can and will oxidise sulfide to harmless sulfate, using the freed oxygen.
I'm not sure what you mean here. What freed oxygen;freed from where?
I disagree. While I think sulfur denitrators are useful and manageable with effort, I think your conclusions about what's going on are off.
Aqua water will alway's contain some nitrate
Nitrogen deficiencies often occur in aquariums. Such a deficiency is likely with a lot of nitrate reduction to dintrate( N2 gas) which can outpace nitrogen inputs form foods,etc. The amount of nitrate reduction does relate to the amount of sulfur being oxidized which relates to the amount of nitrate or free oxygen available .
I don't know why you identified Thiobacillus dentrificans as the main or sole player in a sulfur denitrator; it may be so. It's worth noting ,however,there are many species of bacteria and many sulfur bacteria some of which are used for hydrogen sulfide production for commercial purposes. Nevertheless, since you noted it , let's take a look at Thiobacillus nitrificans and how it acts in a denitrator .
Thiobacillus nitrifcans is a chemolithoautotrophic bacteria. It gets energy from oxidizing an inorganic compound(sulfur).Thus, it doesn't need organic carbon for energy like heterotrophic or photoautotrophic bacteria do.
It needs oxygen in order to oxidize the sulfur.
It is facultative;able to use free oxygen and when it's exhausted nitrate(NO3) for oxygen. When the water becomes anoxic (no oxygen and no nitrate) it can't oxidize the sulfur and can't get the energy it needs to thrive. This sets the stage for sulfur reducing bacterial activty which reduces sulfate(SO4) with toxic hydrogen hydrogen sulfide as a by product.
Thiobacillus denitrificans also needs to uptake some nitrogen via assimilation in order to grow and won't thrive without it. This is from the paper you cited:
(T.denitrificans) can also carry out anaerobic respiration, using nitrate as the terminal electron acceptor, while oxidizing the elemental sulfur to sulfate. However, they lack the ability to synthesize assimilatory nitrate and nitrite reductases, therefore a source of ammonia/nitrogen must be present for cell/protein synthesis to take place.
It also needs some carbon for it's biomass and gets it by fixing CO2 as noted in my previous post.
I think when you just turn up the flow these bacteria will thrive on the oxygen in the water and keep on oxidizing sulfur that way if there is at least enough nitrogen for them to grow. Of course just oxidizing the sulfur to sulfate without nitrate reduciton serves no benefit and can throw the sulfate ;chloride ratios in the tank out of balance over time.
Thiobacillus denitrificans, can and will oxidise sulfide to harmless sulfate, using the freed oxygen.
I'm not sure what you mean here. What freed oxygen;freed from where?
Belgian Anthias
New member
Nitrate
Nitrate
In a normal operated aquarium with a lot of animals there will be alway's nitrate available. There must be. Animal live needs nitrate.
System water must pass the de-nitrator once or twice a day and the amount of sulphur must be +- 1% of the system volume. This is very important . Sulphur quantity must NOT be matched with the amount of nitrate in the water. When the nitrate goes down just increase the flow a bit. When the flow is to high you will find some nitrite in the effluent which is harmless because the amount is very little and it will be oxidized. This is because the de-nitration process was not completed. Once the flow matches the system and the system is balanced a monthly check will do. If feeding or setup is changed, than the effluent flow must be adjusted. A sulphur de-nitrator that becomes anoxic is clogged or the water is tunnelling true the media or there is not enough flow. If a fluidized bed filter is used there is no risk at all and it is the easiest manageable nitrate removal system possible.
If you have not a lot of animals and you have not a lot of nitrate in the water than you do not need a de-nitrator. But if you need one,a sulphur de-nitrator is the best and safest system available.
Remark: a sulphur de-nitrator is SULPHUR + Calcium media. Better two separate reactors.
Nitrate
In a normal operated aquarium with a lot of animals there will be alway's nitrate available. There must be. Animal live needs nitrate.
System water must pass the de-nitrator once or twice a day and the amount of sulphur must be +- 1% of the system volume. This is very important . Sulphur quantity must NOT be matched with the amount of nitrate in the water. When the nitrate goes down just increase the flow a bit. When the flow is to high you will find some nitrite in the effluent which is harmless because the amount is very little and it will be oxidized. This is because the de-nitration process was not completed. Once the flow matches the system and the system is balanced a monthly check will do. If feeding or setup is changed, than the effluent flow must be adjusted. A sulphur de-nitrator that becomes anoxic is clogged or the water is tunnelling true the media or there is not enough flow. If a fluidized bed filter is used there is no risk at all and it is the easiest manageable nitrate removal system possible.
If you have not a lot of animals and you have not a lot of nitrate in the water than you do not need a de-nitrator. But if you need one,a sulphur de-nitrator is the best and safest system available.
Remark: a sulphur de-nitrator is SULPHUR + Calcium media. Better two separate reactors.
System water must pass the de-nitrator once or twice a day and the amount of sulphur must be +- 1% of the system volume. This is very important . Sulphur quantity must NOT be matched with the amount of nitrate in the water.
Why? Seems counter intuitive. I should be able to make it as small as I want and get an effect as small as I want. If I only have a little excess nitrate, why not use a smaller denitrator?
Why? Seems counter intuitive. I should be able to make it as small as I want and get an effect as small as I want. If I only have a little excess nitrate, why not use a smaller denitrator?
I think that is a overly simplistic comment.
Where do you suppose they get carbon atoms for building organic molecules? Must be from somewhere, either other organic molecules, or CO2. In either case, carbon is needed.
If O2 runs out and nitrate runs out, what are the bacteria doing to gain energy? How do you propose they use sulfur to get energy in that scenario?
If you have not a lot of animals and you have not a lot of nitrate in the water than you do not need a de-nitrator. But if you need one,a sulphur de-nitrator is the best and safest system available.
Aside from a carbon denitrator, how is it safer than the other methods folks use:
growing macroalgae
organic carbon dosing (vodka, vinegar, pellets, etc)
live rock and/or sand or porous media
skimming and other ways to remove organics before they degrade
Aside from a carbon denitrator, how is it safer than the other methods folks use:
growing macroalgae
organic carbon dosing (vodka, vinegar, pellets, etc)
live rock and/or sand or porous media
skimming and other ways to remove organics before they degrade
When the flow is to high you will find some nitrite in the effluent which is harmless because the amount is very little and it will be oxidized. This is because the de-nitration process was not completed.
Because when facultative bacteria have free oxygen to oxidize the sulfur ,they aren't using all of the 0 from the nitrate. If flow were even higher very little to no nitrate would be reduced .
Because when facultative bacteria have free oxygen to oxidize the sulfur ,they aren't using all of the 0 from the nitrate. If flow were even higher very little to no nitrate would be reduced .
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Since the reactor will become anoxic with low nitrate and oxygen and will produce hydrogen sulfide in that condition, I found it useful to run the effluent through granulated ferric oxide (GFO) as a safety. The GFO helps accelerate the oxidation of the hydrogen sulfide lessening the potential for toxicity from it in the tank. Randy gave me a tip on that years ago and it worked very well .
Belgian Anthias
New member
Yes, when you have all of these in your system and there is no nitrate production than something is wrong with the bacterial balance. When there is nitrate in the system it proves that all off these elements are or have been available for your animals. If nitrate builds up adjustments in the setup are necessary ( less animals, more live stone etc..) If setup can not or will not be changed a sulfhur de-nitrator can do the job.
No, All living things do not need nitrate;they need fixed nitrogen.
Some organisms prefer ammonia for example and use it ,they don't need nitrate. If the ammonia is taken up, what would oxidize to nitrate? Some consume nitrogen in foods before it degrades to ammonia and oxidizes to nitrate. All living things do not need nitrate;they need fixed nitrogen. The level of nitrate doesn't tell you how much nitrogen is biologically available and being used ;it only tells you how much nitrate there is or isn't. The sulfur bacteria can't use ammonia or organic nitrogen ,Thiobacilllus denitrificans can't use ammonia or other ntirogen sources for the O they need to obtain energy from sulfur.they need O2 ,NO3 or NO2 for that .
Some organisms prefer ammonia for example and use it ,they don't need nitrate. If the ammonia is taken up, what would oxidize to nitrate? Some consume nitrogen in foods before it degrades to ammonia and oxidizes to nitrate. All living things do not need nitrate;they need fixed nitrogen. The level of nitrate doesn't tell you how much nitrogen is biologically available and being used ;it only tells you how much nitrate there is or isn't. The sulfur bacteria can't use ammonia or organic nitrogen ,Thiobacilllus denitrificans can't use ammonia or other ntirogen sources for the O they need to obtain energy from sulfur.they need O2 ,NO3 or NO2 for that .
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Belgian Anthias
New member
The reactor will not and may not become anoxic at low nitrate levels. When nitrate lowers flow is increased a little bit and brings more oxygen in the system. A part of the reactor will always function as a normal biologic filter which depletes the free available oxygen. Than the anaerobic bacteria will take over and do the de-nitration process. Part of them will use the available carbon. So, when the flow increases more oxygen becomes available for the aerobic process and there will be more carbon and less time and place for the anaerobic process. The process can be followed up by measuring the effluent PH and or redox potential. That is one of the reasons two different reactors for sulphur and cacium media are used. In a sulphur de-nitrator the same bacteria can complete both processes. That is why the reactor must be big enough and enough sulfur media must be available, for easy flow management. Flow will never and can not become that low that anoxic conditions may occur. When using fluidized bed reactors anoxic conditions are only possible if the reactor is not manged the way it should.
If a sulfhur de-nitrator is managed wrong and the amount of sulfhur is based on the amount nitrate available flow management becomes impossible and the hobbyist will experience it to difficult to manage. The sulfur de-nitrator is easy to manage and very reliable on the short and long term if managed the right way.
If badly managed the amount of sulfide will always be small and bringing air into the reactor's exhaust effluent will do the job. No extra costs and the advantage that can be smelled something is wrong. Anyway, the exhaust water must always be aerated before passing it true a diakat reactor or bringing it into the system to stabilize the PH.
Rotten egg smell is only noticeable during a bad start up or the reuse of a reactor after being isolated for some time from the system. If a new reactor must be incubated or an old one reused it is best done during a water change, than the effluent of the reactor can be wasted without extra costs.
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