Safe carbon dosing?

[Belgian Anthias]

This is a purely hypothetical question. In case of!
I want to lower the nutrient content in a 2-year-old reef system, lower the nitrate availability. Nitrate is now 40ppm and phosphate is 0,4 ppm. The nitrate level now increases at a weekly rate of +- 4ppm, this since a few weeks. I have no real reason to do this as everything looks fine, I just want to prevent my nitrates will become sky-high.
If possible I would like to target a nitrate level of 2ppm.

I am aware of the fact dosing carbon can not be done without creating side effects and I want to do it as safe as possible, without changing too much as evering is going fine at the moment, except for the nitrate build-up.
Do I base the daily dose on the nitrate level and what should be the target daily nitrate removal rate? And why?
Or is it better to dose based on the phosphate level? And why?
Maybe it is best to dose based on the weekly nitrate accumulation rate?
What are the main caveats I should be aware of before starting dosing and what can I do for limiting the risk or to prevent them to happen?
I am going to use vodka 40%. I do know how much vodka I need to be able to remove 1mg nitrogen.

 

[Belgian Anthias]

Before starting dosing vodka, what are the basic things one must think of, what should certainly be taken into account?
A lot of reefers dose organic carbon based products, for different reasons. Lowering nitrate and or phosphorus? Limiting algae growth? Controlling cyano? Dino's? Feeding filter feeders? Feeding corals? Any other reason?
What are the things, parameters, you take into consideration dosing organic carbon based products?

 

[bar|none]

Bump..I think this is a good question and interested....

I dosed/ (still may on occasion) carbon but just over a few days because I felt like my balance was off, the refugium was not processing nitrate and phos like normal and I was surfing higher levels. It dropped my nitrate back down and also my PO4 back into range like No3 <= 2 PO4< .1, then I stopped and things seemed better.

But I don't claim to know the side effects. I do not dose Carbon, NO3 or PO4 unless at a danger zone and only for an instant. Danger zones being No3 at 0, PO4 at 0. But dosing carbon is more subtle, maybe dangerous. Don't know.

For me Dosing NO3 / PO4 are my emergency temporary fast levers up
Dosing Carbon is my fast lever down, for NO3 at least.

Only when in the danger zone but I want to understand more.

 

[ZoWhat]

10ml 80proof vodka per 100g water volume daily.

Been doing that for 2yrs with great coral health. Someone convinced me to stop for 6weeks and the tank turned ugly so i immediately went back.

Stopping was ignorant bc I cutoff the food source that my super charged good bacteria were living on

$13 / month buying a 1/5th of vodka but it keeps all my coraks happy bc the bad bacteria is eliminated by the super charged good bacteria


.

 

[Belgian Anthias]

10ml 80proof vodka per 100g water volume daily.

Been doing that for 2yrs with great coral health. Someone convinced me to stop for 6weeks and the tank turned ugly so i immediately went back.

Stopping was ignorant bc I cutoff the food source that my super charged good bacteria were living on

$13 / month buying a 1/5th of vodka but it keeps all my coraks happy bc the bad bacteria is eliminated by the super charged good bacteria


.

What do you mean by good and bad bacteria? How good bacteria are supercharged and bad bacteria outcompeted?

I do know fast growing heterotrophs may outcompete slow-growing autotrophs such as nitrifiers.
Are heterotrophs considered to be good bacteria and autotrophs bad bacteria?

Once starting dosing it is difficult to stop?! Something to think about before starting dosing.

Maybe you have dosed enough to outcompete most nitrifiers? If something happens or and dosing is stopped suddenly, what is going to remove the daily ammonia-nitrogen production? It may take a few weeks to reinstall sufficient nitrifying capacity.
Something to think about before starting dosing? How much may be dosed to minimize this problem?

Maybe it is about what is considered to be "good" and what is considered to be "bad"?

 

[ScottB]

When I first began carbon dosing, I was pointed to @Randy Holmes-Farley article on dosing. I think he lays it all out pretty clearly.

Where I have seen people get into trouble is when:
a) they ramp the dose amount too fast
b) keep dosing without measuring and bottom out NO3 (sometimes even PO4, but NO3 moves faster)
c) Pull to many nutrient reduction levers at the same time: Fuge & skim & dose & GFO... and they strip the water and end up in the dino thread.

Reefkeeping Magazine - Vinegar Dosing Methodology for the Marine Aquarium

Reefkeeping ...an online magazine for the marine aquarist.

reefkeeping.com

 

[Belgian Anthias]

I am aware of the fact dosing vodka will not restore the nitrogen balance in the system.
A skimmer removes DOC constantly but very selective and leaves inorganic nitrogen behind. It is normal nitrogen will build up faster as any other essential nutrient, creating an unbalance.
When most phosphorus is taken up by dosing it is not abnormal a lot of nitrates may be leftover, as dosing removes everything in natural proportions. What may happen if more is dosed in an attempt to remove the remaining nitrate?

It is confirmed coral bleaching is caused by phosphorus starvation during periods of increased growth ( increased temp) supported by high nitrogen availability. A situation I try to avoid by keeping the nutrients in balance.

How to avoid essential nutrient starvation when dosing vodka? Something to think about before starting dosing!?

Advice, dosing scheme's and schemas published are based on the nitrate level.

 

[Belgian Anthias]

There is no algae problem in the tank.
Why nitrate-nitrogen may accumulate and is not used up by photo-autotrophs, by algae, dinos, and others? They do not need any organic carbon and retrieve their energy from the light. They have to compete only for CO2 and essential nutrients. Is their growth rate to slow or is their growth limited by the availability of essential nutrients? Or something else?
What may happen after adding vodka? Algae growth will be reduced. Is this good or bad? I think most will say it is a "good" thing but is it?
Is this something to think about before starting adding organic carbon?

To be able to lower the nitrate level, more as the daily nitrate-nitrogen accumulation must be removed daily. In this case +- 0,6 ppm nitrate accumulates daily, adding enough vodka to assimilate 1/4 ppm nitrogen I think should be enough to lower the level. To maintain a certain nitrate level removing the daily nitrogen overproduction daily should be enough.
We do know fast growing heterotrophs prefer to use ammonia-nitrogen as a nitrogen source, some even can not use nitrate-nitrogen as they do not carry the enzyms needed to transform nitrate-nitrogen in usable ammonia-nitrogen.
Fast-growing heterotrophs will use up most ammonia-nitrogen and essential nutrients if their carbon source is unlimited available. Not much will be left over for nitrifying bacteria which may not survive and dissapear and with them the nitrifying carrying capacity which has been installed previously.
How much nitrogen may be removed daily by dosing vodka if I want to prevent most nitrification capacity will be removed?
Is this something to think about before starting dosing vodka?

My goal is to reach and maintain a nitrate level of 2ppm. Will I be able to reduce the nitrate level from 40 ppm to 2 ppm by adding vodka? Doesn't it depend on the availability of other essential nutrients including phosphorus? Will my tank still be the same when I try to reach my goal?

A lot to think about before starting dosing carbon.
And should I not think about what to do and how to if I want to stop dosing and doing this safely?

Starting dosing?!
I certainly will not follow the advice to increase the dose until the nitrate level goes down, keep that dose until the nitrate level is down to 0 and then cut the dose by half! I do have some very good reasons!

 

[Reefology1]

@Belgian Anthias I take it you don't carbon dose, or skim for that matter, I'm guessing by reading this and another one of your threads. How then do you deal with excess N and P?

Thank You

 

[Belgian Anthias]

@Belgian Anthias I take it you don't carbon dose, or skim for that matter, I'm guessing by reading this and another one of your threads. How then do you deal with excess N and P?

Thank You

Nitrate production is in relation to the C:N ratio ( the protein content) of the food added to the system.

Organic Carbon dosing ( adding carbohydrates ) does NOT deal with N and P, it removes nothing. The removal rate is based on the the removal rate of the skimmer that may be estimated to be max +-35% , very selective and not reliable.
Ammonia directly released in the tank not all can be removed because part of other essential nutrients needed for growth are exported by the skimmer.
Excess N and P? What about all other essential nutrients? Why N and P may build up in a well lit aquarium and is not used up by algae and other photo-autotrophs?
N is easily exported using BADES columns. ref: MB BADESS CMF De Haes 2007 - 2017
Personally I prefer AAM , active algae management, the nutrient export can be managed ( harvested) as desired by the user and the nutrient balance can be restored by providing for the target nutrient modified feedmedium. In the case using a skimmer is not essential or desired.

Cultivating macro algae in a refuge one may pre-condition the system to the coming bio-load, for example by conditioning the biofilter to assimilate 1 ppm nitrogen daily. Using AAM P is exported in its natural relation to N but the removal of N or P can be managed as desired using a for the target nutrient modified feed medium. if the N availability increases most macro algae will take up more N , increasing the N/P ratio.

This way one never has to deal with excess N and or P. I advise to keep the nutrient reserve including DOC as low as possible preventing the nutrient reserve may become responsible for P to become the growth limiting factor.

Happy reefing.

 

[Reefology1]

On a heavily fed aquarium, how large of a refugium are we talking about (% to display)? Some hobbiest may not have space to accommodate such a refugium. How about an ATS?

 

[Belgian Anthias]

On a heavily fed aquarium, how large of a refugium are we talking about (% to display)? Some hobbiest may not have space to accommodate such a refugium. How about an ATS?

The thread is about safe carbon dosing, if possible. In a closed environment any sudden changes made to the natural C:N ratio's will have consequences for the existing balance, will have an effect on the coral holobiont and everything else and this may lead to the unexpected or unwanted.
I try to limit and avoid sudden changes in a reef display tank by using a refuge. A refuge can be used for all process we want to take place, without much influence on the natural balance created in the display tank, this if one has taken the precautions needed.
In a refuge organic carbon can be dosed without direct influence on the C/N ratio in the display, for cultivating biofloc, a possible solution for very heavily fed marine aquarium and aquaculture systems or and HI/HO mixed reef systems

Nitrogen and nutrient management starts with the protein content and origin ( marine) of the food added, important in heavily fed aquarium and other closed systems. On may remove particulate food particles from the display tank very fast after being added ( HI/HO), and take the time to brake them down, remove and or reuse them. This way feeding filter feeders without overloading the display water with DOC. For this I need bio-filtration in a refuge.

Info asked is made available in references previously added.

One can not use AAM in a display with corals, because one has to be able to feed in function of algae growth or and other growth targeted,.That is why I use a refuge. It is the intention all nutrients added to the refuge are used up in the refuge, leaving cleared water for the display, I do advise the combination of AAM with remineralization filters for stimulation of complete bio-remineralization, removing most DOC, using bio-columns and or plates that can be placed ( hanged up) in a refuge. ( sump?) Such columns and plates easily can be made and applied.

A lot of hobbyists have space for a sump. Hobbyists not having the space for bio-filters are advised to limit the bio-load, to an LNS, and to keep the dream for a mixed reef system alive.
I do not have the experience using an ATS for AAM. One can put an ATS in a refuge but in the case it would be a waste of money. Maybe there are solutions using an ATS for AAM ( active aquarium management) but I leave this for ATS users to find out.
For AAM I advise to install the growth rate needed using only 50 % of the max capacity of the refuge, this way the filter may grow with the system. Because we do not need to use the best performers we can focus on algae suitable for to be reused as a food source, which in general do not produce much toxins.
One may learn to use AAM in a separate tank and connect this tank later to the system to become a refuge.
This way a new system can be conditioned in advance for what is coming. In the case the display can be connected after being cycled and is able to support bio-load in function of the already installed carrying capacity, this if the remineralization filters already have been conditioned in combination with the algae in the refuge.

Algae are slow growers and are not able to provide the carrying capacity ( ammonia reduction rate ) needed for heavily fed aquaria. For this remineralisation filters are used, also providing the nitrification capacity needed to remove produced ammonia. The safely stored nitrogen (nitrate) is then used for the growth needed to clear the water from inorganic nutrients.

The nitrate production ratio can be managed using the C/N ratio of organic food added and coming back to safe carbon dosing, carbon dosing may provide very fast ammonia removal.
In the case we must be able to harvest heterotrophic growth, biofloc. Mesh filters may be used in a remineralisation chamber ( refuge) to harvest produced protein, particulate TOC, that also can be reused as a food source.

In a heavily fed reef aquarium one is able to provide the water quality needed, managing heterotrophic and autotrophic growth, but not all nutrients can be removed by growth and be harvested if a skimmer is used,. Using AAM the nutrient unbalance created by a skimmer can be restored. An other solution is not using a skimmer in combination with bio-filtration and nutrient export based on harvesting growth.

 

[Reefology1]

Thank you for the detailed answer, I appreciate you taking the time.

 

[Randy Holmes-Farley]

Organic Carbon dosing ( adding carbohydrates ) does NOT deal with N and P, it removes nothing. The removal rate is based on

Ignoring the comment about carbohydrates, which I have never suggested folks use, simple carbon dosing (such as acetic acid or ethanol) is a fine way to reduce nitrate. No english speaking chemist considers either ethanol or acetic acid to be a carbohydrate, so let's not go down that rabbit hole again.

To claim carbon dosing removes nothing is misleading in the extreme.

Acetic acid and ethanol spur many organisms to grow more, and as they grow they add tissue and that added tissue permanently removes N and P from the water (at least as long as that organism remains alive).

 

[dedragon]

An adequately sized protein skimmer (havent seen a mention of one yet) might help as well, just to get some of the excess nutrients out. Also pretty sure its beneficial if carbon dosing as well, for O2 benefits and excess bacterial removal

 

[Belgian Anthias]

Ignoring the comment about carbohydrates, which I have never suggested folks use, simple carbon dosing (such as acetic acid or ethanol) is a fine way to reduce nitrate. No english speaking chemist considers either ethanol or acetic acid to be a carbohydrate, so let's not go down that rabbit hole again.

To claim carbon dosing removes nothing is misleading in the extreme.

Acetic acid and ethanol spur many organisms to grow more, and as they grow they add tissue and that added tissue permanently removes N and P from the water (at least as long as that organism remains alive).

Carbon does does removes nothing FROM THE SYSTEM. On the long term it removes nothing as everything will be recycled .
Nothing is exported from the system and it burdens the bioload and the load-bearing capacity. Telling carbon dosing does removes nutrients is telling lies, it is not true. Growth removes nutrients only if harvested.

Strarch in food and the cellulose is ne


Also in English countries ethanol is a carbohydrate as explained in English manuals used everywhere in the world . ( Chemical Principles The quest of inside Peter Atkins and Loretta Jones; CHEMISTERY by Mc Murray Fay ) it is a bound between We already had this discucssion.

 

[Randy Holmes-Farley]

lol

Please do not cloud the debate with chemical definitions that you are misusing. It is just like the false claim that carbonic acid is an organic molecule just because it contains C and H. Books have that definition too, but that doesn't mean it applies to every case. Chemists (native english speakers, anyway) do not refer to ethanol as a carbohydrate, and when scientists report what carbohydrates do, they are NOT EVER referring to ethanol.

If you google "Is ethanol a carbohydrate" the #1 hit is a paper that says in its abstract:

"Carbohydrate, and not ethanol, induced lipogenic enzymes.":


Besides, I recommend acetic acid over ethanol for dosing anyway.

 

[ReefGeezer]

Seems the OP's original question was just a troll, but just in case it wasn't...

I carbon dose (Vinegar) to promote growth of bacteria that provide a little diversity, and possibly another thread in the food web. Some of the bacteria are removed by the skimmer which also DOES export the N&P bound in their tissue. Additionally, the N&P bound in their tissues and in the new compounds the additional available carbon allows to form are not available to organisms that only use inorganic N&P i.e. pest algae. Organisms consume the bacteria and organic compounds that also host algae and make N&P available for them. These organisms re-mineralize excess N&P so the balance is not really eschewed too much before new carbon sources bind them... at least not for long.

I do see a down-side in that transitional ammonia (that available before being oxidized or bound) is limited and initially affects preestablished balances. I do think that balance is soon readjusted to the new available available ammonia levels. Increasing feeding is my answer to the ammonia limitation. That is also a good thing for my fat & happy fish. A problem can be encountered when stopping carbon dosing. A weening period and possibly a reduction in feeding is needed to let the system readjust.

 

[Belgian Anthias]

Ignoring the comment about carbohydrates, which I have never suggested folks use, simple carbon dosing (such as acetic acid or ethanol) is a fine way to reduce nitrate. No english speaking chemist considers either ethanol or acetic acid to be a carbohydrate, so let's not go down that rabbit hole again.

To claim carbon dosing removes nothing is misleading in the extreme.

Acetic acid and ethanol spur many organisms to grow more, and as they grow they add tissue and that added tissue permanently removes N and P from the water (at least as long as that organism remains alive).

If you did not advise to use carbohydrates, as a chemist, how would you define in one word the compounds only containing carbon, hydrogen and oxygen you did suggest to use?

Ethanol, acetic acid ( vinegar) are the carbohydrates I am talking about!! Obviously we are talking about the same organic compounds.
Starch in food and the cellulose in grass is nearly pure carbohydrate. The word was originally used to describe glucose, Acetic acid C2H4O2 does fulfill the definition of a carbohydrate with the empirical formula CH2O, a hydrate of carbon. ( Chemical Principles The quest of inside Peter Atkins and Loretta Jones; CHEMISTERY by Mc Murray and Fay )
In English countries chemists are using the same manuals cited, used in universities all over the world , also published and used in the US .
Acetic acid, ethanol, sugar, are carbohydrates , the organic carbon compounds we talk about when talking about carbon dosing . Changing the terminology does not change a thing about the result and consequences of adding these compounds to a closed marine aquarium , a reef system.

I think we already had this discussion.

Carbon dosing does remove very little nitrate because when using nitrate as a nitrogen source heterotrophs can not grow fast and are not able to out-compete fast growing photo-autotrophs for nitrate-nitrogen. Fast growing heterotrophs use ammonia, not nitrate.
Suggesting adding carbohydrates is a fine way for removing nitrate is totally on your account , not on mine. How can this claim be scientifically substantiated not ignoring all the known side effects including killing corals ?

Growth removes N and P only if harvested, otherwise it will be recycled.
A skimmer is able to export some of the cultivated growth, about 1/3. About 2/3 will stay behind.

In time It may reduce the addition of food needed, but the total need will increase. The solution is harvesting.

Simple Carbon dosing is using carbohydrates .
There are better and less intrusive options to manage the availability of safely stored nitrogen and of other nutrients.

 

[Belgian Anthias]

Carbon does does removes nothing FROM THE SYSTEM. On the long term it removes nothing as everything will be recycled .
Nothing is exported from the system and it burdens the bioload and the load-bearing capacity. Telling carbon dosing does removes nutrients is telling lies, it is not true. Growth removes nutrients only if harvested.

Strarch in food and the cellulose is ne


Also in English countries ethanol is a carbohydrate as explained in English manuals used everywhere in the world . ( Chemical Principles The quest of inside Peter Atkins and Loretta Jones; CHEMISTERY by Mc Murray Fay ) it is a bound between We already had this discucssion.

this answer was not finished and has been rewritten and may be removed.