I answered the question asked in OP topic, I did not start the discussion about what are carbohydrates. That is solved out.
I replied to remarks made on my explanation. It is not way off-topic, as it is all about adding vinegar in a closed system, carbohydrates that may accumulate as it may not be used up due to unavailability of essentials, information which can be retrieved from the known parameters in topic
How long it will take to see the effect on the nitrate level by adding vinegar in this case? Well, I do not know!
Having a tank with the parameters in this topic, the user should never be advised to dose organic carbon, acetic acid.
Taking into account the known caveats and being aware of what is needed for growth, carbohydrates can be dosed safely. Denial for known caveats does help nobody.
If adding organic carbon has little or no influence on the nitrogen content that should ring the alarm bell!
An overdose of organic carbon has a huge effect on the coral holobiont, much more as the nitrate level ever may be able to. (
ref: MB anthias 2019 ) Nitrate does not harm a thing!
If starting dosing one should also know how to stop dosing in a safe way.
Stopping dosing or reducing doses after having being used for a period of time may cause a so-called "new tank syndrome" Nobody will be able to link it to carbon dosing at the moment the tank is going down. It may not show by the parameters at that moment. Limiting the risks as much as possible is good management.
Building of dosing and or doses must be done over a long period of time, the time needed to reinstall the by carbon dosing replaced autotrophic carrying capacity, which may take weeks.
Managing the nutrient content in a closed system is about knowing what is going in and knowing what is going out.
Answering the question of the topic correctly is not possible as carbon dosing can not directly be linked to nitrate removal. Cultivated r-strategists and other microorganisms relaying on DOC for their carbon source prefer ammonia-nitrogen. Increasing the C/N ratio limits the nitrification capacity, removing autotrophic carrying capacity. Making an estimate about nitrogen export is difficult as
carbon dosing removes nothing from the system, it only increases the heterotrophic bioload which also can be done safely using an algae filter., with a lot fewer drawbacks and a lot lower risk factor. Using an algae filter in a refuge one can estimate and manage the removal rate, one is able to restore and manage the nutrient imbalance created by the use of a skimmer..
Using remineralization filters, one can determine the correct dose of organic carbon needed to produce the energy needed ( using up the added carbon) to take up all nutrients coming available breaking down DOC, nitrate and phosphorus. Which leaves nothing for autotrophic growth. ( algae) This eliminates the use of a skimmer.
One can manage the availability of building materials and add what is needed.
Biofloc is harvested and ore reused as a food source. A high DOC content, a High C/N ratio, a high CO2 production taking place in the display is avoided. Carbon doses are used up in the filter, the high CO2 production is removed and the effect on alkalinity can be corrected before entering the display,
In this case, it is known there is no phosphate reserve for supporting the growth needed to lower the safely stored nitrogen reserve. Heterotrophic growth needs 40x more phosphate and other essentials to install the same carrying capacity supported by autotrophs, to reduce the same amount of ammonia. ( ref;
MB CMF De Haes 2017) This means the bioload must be able to increase considerably and must continue to increase to support the carrying capacity.
Once started dosing one has to continue dosing.
A skimmer removes essential building materials (DOC ) constantly but leaves inorganic nutrients behind, it must be clear organic carbon is easily overdosed using the inorganic nitrogen reserve as a guideline for dosing. Acetic acid does not contain essentials needed to support growth, for restoring the created nutrient unbalance, only carbon for energy production. If the essentials are not available the system is overdosed, which may show by the snow effect when nutrients suddenly become available, depleting the oxygen content and creating a sudden and periodically high CO2 production and pH dip. On fora, this is often not considered a drawback of carbon dosing. Try to explain this to your corals and its holobiont. To everything else present in the system.
In this case, the nitrate level can not go down without messing up the biological balances in the entire tank. It will take its time. An inexperienced and not correctly informed user will start to increase doses in an attempt to lower safely stored nitrogen which can not be used at the moment of dosing due to the unavailability of the essentials needed for growth, ending up creating a huge overdose.
Other and safe solutions for managing the nutrient content have been mentioned.
Thanks for reading. Happy reefing!