Nitrate and the BIO filter!

[Belgian Anthias]

Huh? Can't be done?

I ran a non ULNS system for 20 years using several fine methods to control nutrients, including growing macroalgae and organic carbon dosing. It does not become ULNS unless you overdo any of these methods.

Why not? With a new BADES bio reactor or a BADES filter one can double or triple the live support capacity within 20 days. When conditioned sulphur is used less than 10 days. No nitrate in the water as produced ammonia nitrogen is immediately removed.

 

[Randy Holmes-Farley Verified Community Expert]

Why not? With a new BADES bio reactor or a BADES filter one can double or triple the live support capacity within 20 days. When conditioned sulphur is used less than 10 days. No nitrate in the water as produced ammonia nitrogen is immediately removed.

What are you assuming is limiting the life support capacity? IMO, it is not typically nitrate levels.

 

[Belgian Anthias]

What are you assuming is limiting the life support
capacity? IMO, it is not typically nitrate levels.

Size of the tank? Size of the biofilter? Spotte published a formula to calculate the caring capacity of a system in 1979. (SHSpotte1979>Spotte, S., 1979. Fish and invertebrate culture: water management in closed systems, 2d ed. ed. Wiley, New York.) The capacity to reduce ammonia! Nitrate and nitrate levels have no or little influence on the total capacity except when there is to much. Denitrators or nitrate removal methods do not increase the live support capacity of an aqua culture system. An algae scrubber does increase the capacity as it assimilates NH3
Aquaculture systems don't use live rock!

 

[Randy Holmes-Farley Verified Community Expert]

Size of the tank? Size of the biofilter? Spotte published a formula to calculate the caring capacity of a system in 1979. (SHSpotte1979>Spotte, S., 1979. Fish and invertebrate culture: water management in closed systems, 2d ed. ed. Wiley, New York.) The capacity to reduce ammonia! Nitrate and nitrate levels have no or little influence on the total capacity except when there is to much. Denitrators or nitrate removal methods do not increase the live support capacity of an aqua culture system. An algae scrubber does increase the capacity as it assimilates NH3
Aquaculture systems don't use live rock!

In my opinion, the safe size of the number of fish in a reef tank is more limited by what happens in an emergency (such as a power failure), than in what happens during normal operation.

 

[Belgian Anthias]

In my opinion, the safe size of the number of fish in a reef tank is more limited by what happens in an emergency (such as a power failure), than in what happens during normal operation.

Animals are introduced, they grow and multiply and produce waist, one can not stop this. An aquarium system should be able to grow with its habitants which is easily done by adding biofilter(s) Keeping a reef aquarium, which is quite an investment, holds the responsibility for its habitants. A power failure should not be an emergency. When an emergency occurs one does normally know what went wrong. Most problems will occur during normal operation and when its happens most will not know why. System crashes due to a water change? Removing nutrients? Everything is possible but most of the problems have to do with an interruption of the nitrogen and/or carbon cycles which are the carriers of the system.

 

[Belgian Anthias]

I thought it over but still don't get it how carbon dosing in a reefaquarium can be neutral for alkalinity.

In a Belize system, a zero emission system where heterotropic ammonia reduction is used , we start with NH4 or NH3 and after dosing carbohydrates the following protein production is enriched and used as food . We end up with NH3 >NH4. and we can start again. When the cultivated scrimp stop growing they are harvested. Alk is consumed and must be corrected regularly. There is no nitrate production in a Belize system. A problem is the high production of CO2 but this is resolved by aeration needed for the high oxygen demand. A Belize system is a freshwater system.


In a reef aquarium we start with NO3 , carbohydrates are added and protein produced by which alk is consumed. Say 80% of this protein is taken up as food and 20% removed. From this 80% +- 20% is used for growth and 80% released as NH3 which may be transformed to NH4 This NH4 and NH3 is then nitrified to NO3 by which a lot of alk is consumed. As this nitrate production is the result of the carbon dosing it must be taken into account because the next carbohydrates dose will be based on the presence of it. The cycle formed by carbon dosing in a reef aquarium thus include nitrification!
A lot of users of this method may think that most of the produced protein is removed. Say we follow that line, how the consumed alk is compensated? I suppose that the produced CO2 is removed?

 

[Randy Holmes-Farley Verified Community Expert]

I’m waiting in a jury room for jury duty and can’t do long explanations on my phone right now, but there is no net change in alkalinity when a neutral organic molecule such as an uncharged protein is fully metabolized with O2 to CO2, water and NH3. There need be no other products, and since there are no charges present, there can be no impact on alkalinity.

The same is true of the opposite reaction, as happens in macroalgae,

 

[Randy Holmes-Farley Verified Community Expert]

Yes, alkalinity in consumed in nitrification. Denitrification gives back exactly the alkalinity that was lost during nitrification.

 

[Belgian Anthias]

Yes, alkalinity in consumed in nitrification. Denitrification gives back exactly the alkalinity that was lost during nitrification.

Correct, but:
When no sulphur is added in a normal biofilm growing on sand only +- 35% of the nitrate produced can be removed of which +-25% heterotropicaly. In this case we are talking about the nitrate produced because of carbon dosing. Carbon is dosed because the denitrifying capacity is fully used already. When more nitrate is produced this must be removed by an other dose of carbon and will not be removed by denitrification except when some sulphur is added. As nitrification is part of the carbon dosing cycle I am pretty sure that alkalinity is depleted because of carbon dosing.

Changing the C:N ratio a bit by carbon dosing thus not change a lot to the hetertropic denitrification ratio as the anoxic zone in an aerobe biofilm is limited. Autotropic sulphur bacteria do not need an anoxic zone to start anaerobic methabolismn and are able to reduce nitrate long before heterotropic bacteria can. One must not only see these zones as a layer but also as that particular place where the reactions take place. BADES works fine in an OMZ ( oxygen minimum zone), that is a zone where the oxygen is consumed faster as it can be supplied. These zones are are not suitable for heterotropic denitrification.


Normal denitrification in the oceans is autotropic!

 

[Randy Holmes-Farley Verified Community Expert]

As nitrification is part of the carbon dosing cycle I am pretty sure that alkalinity is depleted because of carbon dosing.

I just don't see any basis for thinking there is any process whereby organic carbon dosing depletes alkalinity.

What is that process exactly? Can you write it as a chemical equation?

 

[Randy Holmes-Farley Verified Community Expert]

As a follow up, How does your assertion that organic carbon results in depleted alkalinity match with the fact that much of fish food is organic carbon?

 

[Forsaken77]

It's like they're speaking Klingon to me. Whew... Way over my head.

 

[Belgian Anthias]

I just don't see any basis for thinking there is any process whereby organic carbon dosing depletes alkalinity.

What is that process exactly? Can you write it as a chemical equation?

I am not a chemist! I get my knowledge from the research of others including you.

Everything is written down in the Makazi Baharini which wast first set up as our personal knowledge base. Since a few years I am transferring everything into readable text including the references. The wiki is written in Dutch but a lot of pages are translated to English. The translation is going on. The references, which can be consulted, are in the original language mostly in English.

When adding carbohydrates one must not look only to the chemical process of assimilation ( without decay), which may consume alk. (Ebling2006), this is proved in practise ( Belize system), but also at all the other chemical processes caused by the action of dosing these carbo hydrates. In a reef aquarium this includes the nitrification process. Declaring that carbon dosing is neutral for alk is closing the eyes for what really happens due to adding the carbo hydrates in a reef aquarium. In fact adding carbohydrates is no more than creating food with what was processed and left over from a previous feeding and there is nothing wrong with that. This food goes true the normal nitrogen cycle including the fact that when carbon is dosed in a reef aquarium we start from NO3 and end up with biomass and NO3. Carbon dosing by it selves removes nothing from the system! The normal nitrogen cycle is from mineralisation > NH4 to N2 > removed, back to where it came from. For the rest it is the same process as for any food added in a reef aquarium, it is consumed, secreted, a part is removed by a skimmer and in a BADESS the rest is removed from the system.

It is wrong to say that nothing is removed when carbohydrates are added, as lefts over from previous feeding which are assimilated may be removed by a skimmer. But this is not caused by the carbon dosing and is not included in the carbohydrates dosing cycle.
Sugar, vinegar and vodka are not only carbohydrates, what happens with the rest of these compounds can be discussed but what about the effect on the long term ?

Anyway, carbon dosing does not solve the problem of the left overs and creates a cycle which includes nitrification. Adding 1 gram of carbohydrates has the same effect on alk as adding 20 grams food with 35% protein. No effect all when the nitrogen cycle is in balance, but the fact that one is dosing carbohydrates proves that it isn't.

 

[Randy Holmes-Farley Verified Community Expert]

I'm sorry, I'm not following your logic, and what I can understand I disagree with.

I do not know of any process in a reef aquarium that is driven by adding, say, acetic acid or ethanol, that depletes alkalinity.


"When adding carbohydrates one must not look only to the chemical process of assimilation ( without decay), which may consume alk.(Ebling2006), this is proved in practise ( Belize system), but also at all the other chemical processes caused by the action of dosing these carbo hydrates. In a reef aquarium this includes the nitrification process. Declaring that carbon dosing is neutral for alk is closing the eyes for what really happens due to adding the carbo hydrates in a reef aquarium."

I think I understand what can happen to these molecules in a reef aqaurium, and none of those processes result in a loss of alkalinity.

 

[Belgian Anthias]

I'm sorry, I'm not following your logic, and what I can understand I disagree with.

I do not know of any process in a reef aquarium that is driven by adding, say, acetic acid or ethanol, that depletes alkalinity.


"When adding carbohydrates one must not look only to the chemical process of assimilation ( without decay), which may consume alk.(Ebling2006), this is proved in practise ( Belize system), but also at all the other chemical processes caused by the action of dosing these carbo hydrates. In a reef aquarium this includes the nitrification process. Declaring that carbon dosing is neutral for alk is closing the eyes for what really happens due to adding the carbo hydrates in a reef aquarium."

I think I understand what can happen to these molecules in a reef aquarium, and none of those processes result in a loss of alkalinity.

I am shore of that. But I am not only talking about that process that is driven by carbohydrates, I am talking about the cycle of processes caused by adding them en the result of all these processes. The result of all these processes is that Alk is depleted ! One must not measure it to know this.

Part of the nitrification process that is taken place in an aquarium where carbohydrates are added is caused by the fact of adding the carbohydrates,, as adding more food will produce more nitrate in a system where the nitrogen cycle is out of balance. Adding carbohydrates does not correct this balance. The alkalinity measured in the water column is the sum of all these processes. When the carbohydrates where not added the depletion as a result of nitrification would be less. And worse, one creates a continues cycle from ammonia that was already nitrified (NO3) to ammonia that must be nitrified to NO3, every cycle causing consumption of alk which would not happen when carbohydrates are not supplemented.
All the above can be avoided by simply remove the nitrate or avoid that nitrate enters the water column instead of cycling it. By adding a biofilter with sulphur as a base for a growing biofilm this is easily done which brings me back to the subject of the threat.

 

[Belgian Anthias]

To go back to the threat, we want to reintroduce the biofilter. This way we can adjust the carrying capacity of a system to our wishes. Any time! When a normal biofilter is introduced a denitrator is necessary to remove the produced nitrate and we want to avoid the use of a denitrator. We found the solution by providing sulphur as the base for a growing aerobe biofilm. How this works was explained in previous replies.

A BADES biofilter or - reactor does not change the Alk measured in the water column and ads calcium. This is the result after nitrification and denitrification within the same biofilm. No supplements for correction off alk are needed because of the completion of the nitrogen cycle. Calcium production is not a problem as the calcium is consumed by calcification. Calcification leads to depletion of alk which must be corrected but the total correction is less as nitrification and denitrification is already compensated. The calcium production is high as both nitrification and denitrification will lead to the production of calcium.
A nitrifying biofilm growing on chalk will not influence alk in the water column and produce calcium!

Calcium brings me to my question. Autropic denitrification produces sulphate. In some fresh water treatment plants using BADES on a mix of oyster grid and sulphur granulate ( SLAD systems) plaster is formed in the reactor . ( Ph 6-7) I could not find any report of this using seawater despite the high calcium and sulphate already present. It is reported that maerl is taking up sulphate but nothing about the production of plaster. As the calcium production is double compared to a SLAD system it is a concern. I would appreciate your advice about this. Can the production of calcium and sulphate on the same place lead to precipitation of plaster in a seawater aquarium? I know kalkwasser is used to reduce high sulphate concentrations in fresh water treatment plants and how it is done.

 

[Randy Holmes-Farley Verified Community Expert]

A BADES biofilter or - reactor does not change the Alk measured in the water column and ads calcium. This is the result after nitrification and denitrification within the same biofilm. No supplements for correction off alk are needed because of the completion of the nitrogen cycle. Calcium production is not a problem as the calcium is consumed by calcification. Calcification leads to depletion of alk which must be corrected but the total correction is less as nitrification and denitrification is already compensated.

I agree with that.

Calcium production is not a problem as the calcium is consumed by calcification.

That is an opinion that I do not share. If you frequently monitor and adjust calcium dosing to offset this effect, then it is a problem that can be overcome.

If you chose to use a balanced method such as a CaCO3/CO2 reactor to add calcium and alkalinity, the calcium will climb and is only held back by water changes you might do.

It is essentially unbalanced dosing of calcium.

Calcium brings me to my question. Autropic denitrification produces sulphate. In some fresh water treatment plants using BADES on a mix of oyster grid and sulphur granulate ( SLAD systems) plaster is formed in the reactor . ( Ph 6-7) I could not find any report of this using seawater despite the high calcium and sulphate already present. It is reported that maerl is taking up sulphate but nothing about the production of plaster. As the calcium production is double compared to a SLAD system it is a concern. I would appreciate your advice about this. Can the production of calcium and sulphate on the same place lead to precipitation of plaster in a seawater aquarium? I know kalkwasser is used to reduce high sulphate concentrations in fresh water treatment plants and how it is done.

You will want to do water changes to prevent a rise in sulfate and a depletion in chloride (which happens when you maintain salinity, if sulfate rises chloride must fall).

Limewater has no effect on sulfate in seawater.

Calcium sulfate is pretty soluble in seawater and I do not think precipitation is the primary concern from rising sulfate.

 

[Randy Holmes-Farley Verified Community Expert]

I am shore of that. But I am not only talking about that process that is driven by carbohydrates, I am talking about the cycle of processes caused by adding them en the result of all these processes. The result of all these processes is that Alk is depleted ! One must not measure it to know this.

I do not agree. It is depleted. How would it? lol

Part of the nitrification process that is taken place in an aquarium where carbohydrates are added is caused by the fact of adding the carbohydrates,, as adding more food will produce more nitrate in a system where the nitrogen cycle is out of balance.

Why would adding acetic acid or ethanol increase nitrification? How could it? You are not adding nitrogen.

Part of the nitrification process that is taken place in an aquarium where carbohydrates are added is caused by the fact of adding the carbohydrates,, as adding more food will produce more nitrate in a system where the nitrogen cycle is out of balance. Adding carbohydrates does not correct this balance. .

It essentially drives the incorporation of nitrogen into organic matter. Sources of that N might be ammonia or nitrate. Neither process results in any depletion of alkalinity.

When the carbohydrates where not added the depletion as a result of nitrification would be less. And worse, one creates a continues cycle from ammonia that was already nitrified (NO3) to ammonia that must be nitrified to NO3, every cycle causing consumption of alk which would not happen when carbohydrates are not supplemented.
.

No. That is a totally incorrect assertion and may be the basis of our disagreement.

Ammonia to organic matter and back to ammonia has ZERO impact on alkalinity (nitrogen is in the same oxidation state in ammonia and in organics such as a protein), and that result does not depend on whether the ammonia was converted into nitrate before incorporation into organic matter or not. if you convert it first into nitrate, you lose alkalinity, and then you get that same alkalinity back again if you convert it into either ammonia or organic matter.

 

[Belgian Anthias]

I agree with that.



That is an opinion that I do not share. If you frequently monitor and adjust calcium dosing to offset this effect, then it is a problem that can be overcome.

If you chose to use a balanced method such as a CaCO3/CO2 reactor to add calcium and alkalinity, the calcium will climb and is only held back by water changes you might do.

It is essentially unbalanced dosing of calcium.



You will want to do water changes to prevent a rise in sulfate and a depletion in chloride (which happens when you maintain salinity, if sulfate rises chloride must fall).

Limewater has no effect on sulfate in seawater.

Calcium sulfate is pretty soluble in seawater and I do not think precipitation is the primary concern from rising sulfate.

Precipitation of plaster is a major concern as it could clog the filter.
Calcium production will be only only+-1/10 of what we expect that may be consumed by calcification. It will not be a problem to use a balanced method en from time to time do a small correction if necessary. As in any reefaquarium.

Sulphate isn't a mayor concern for me as the rise of the total sulphate will be limited and it will take a few years to produce enough sulphate to fill up the difference in sulphate between commercial sea salt brands which was from 15mmol to 37mmol/kg( Bingman1999) As it is not a major concern for the sea salt manufacturers .
In the MAAO where 800kg sulphur and the same amount of maerl is used they have little problems with sulphate build up as the maerl takes up till +-200g sulphate/kg maerl ( Hignette 2001)
The sulphate is removed when the maerl is renewed. Hignette does not speak about precipitation. The sulphate is held back by the maerl? As we plan to renew the lime at least every year this should not be a problem.

M.Longouet kept corals for several years without any water change in an aquarium system with sulphur denitrators.I think it was seven years,

Salinty!? That is an issue I overlooked and did not examin. I must look into that one. Thanks! I do not immediately see this as a problem. The rise of sulphate will be modest compared to the amount already present. Even when sulphate is not held back by the lime I suspect a rise of max 10% within 3 month but it could become a problem on the long term when a high sulphate salt mix is used. I don't know if this needs correction but I will look into it. ? How much sulphate is acceptable, or chloride depletion? We do not suspect to do water changes only for sulphate build up.

 

[Randy Holmes-Farley Verified Community Expert]

Precipitation of plaster is a major concern as it could clog the filter.
Calcium production will be only only+-1/10 of what we expect that may be consumed by calcification. It will not be a problem to use a balanced method en from time to time do a small correction if necessary. As in any reefaquarium.

Sulphate isn't a mayor concern for me as the rise of the total sulphate will be limited and it will take a few years to produce enough sulphate to fill up the difference in sulphate between commercial sea salt brands which was from 15mmol to 37mmol/kg( Bingman1999) As it is not a major concern for the sea salt manufacturers .
In the MAAO where 800kg sulphur and the same amount of maerl is used they have little problems with sulphate build up as the maerl takes up till +-200g sulphate/kg maerl ( Hignette 2001)
The sulphate is removed when the maerl is renewed. Hignette does not speak about precipitation. The sulphate is held back by the maerl? As we plan to renew the lime at least every year this should not be a problem.

M.Longouet kept corals for several years without any water change in an aquarium system with sulphur denitrators.I think it was seven years,

Salinty!? That is an issue I overlooked and did not examin. I must look into that one. Thanks! I do not immediately see this as a problem. The rise of sulphate will be modest compared to the amount already present. Even when sulphate is not held back by the lime I suspect a rise of max 10% within 3 month but it could become a problem on the long term when a high sulphate salt mix is used. I don't know if this needs correction but I will look into it. ? How much sulphate is acceptable, or chloride depletion? We do not suspect to do water changes only for sulphate build up.