NEW Vodka and Vinegar Dosing Charts

[rc1]

I am in my 3rd and getting ready to increase the vinegar dosing to 200ml and see if that does anything.

 

[aquadise]

Can i use Glacial Acetic Acid 99.5% instead?

 

[Randy Holmes-Farley]

Can i use Glacial Acetic Acid 99.5% instead?

Yes, assuming it has reasonable purity fir things like metals.

 

[pwfess]

The reasons I'm updating the Vinegar and Vodka dosing charts are two-fold:

1. The ramp was unnecessarily slow. There was no perceived benefit to such a tedious ramp, and it led to reefers quitting because they thought carbon dosing didn't work.

2. The ramp did not scale up correctly at all. A 40x larger tank only received 2x the needed dose. (A 1,000-gallon tank only received twice the dose of a 25-gallon tank).


Carbon dosing is a fantastic way to lower nutrients, more specifically nitrate. The reason is three-fold:

1. Organisms, such as bacteria, contain much more nitrogen than phosphorous.

2. Denitrification is a process that happens in anaerobic conditions (little to no oxygen). These bacteria require an organic to oxidize the nitrate molecule (NO3-) into Nitrogen (N2). They use the oxygen that is attached to the nitrate molecule to respire. Thus, there will be NO phosphate consumed during this process.

Here is the equation by @Randy Holmes-Farley :

organic + 124 NO3– + 124 H+ → 122 CO2 + 70 N2 + 208 H2O

3.We have an immense reservoir of phosphate bound to calcium carbonate rocks and sand. To put to pespective, a 50% water change with nutrient-free water will successfully reduce your nitrate values by 50%. More often than not, the phosphate value will climb right back up near the starting point after a day; PO4 tries to be in constant equilibrium with the bulk water column and calcium carbonate surfaces.


For these reasons, I do NOT recommend dosing carbon solely for controlling phosphates. It is likey to deplete nitrate before seeing phosphate mildly decrease.

What are the benefits of carbon dosing?

Besides reducing nitrate, spurring bacteria is the main benefit. This bacteria can feed many organisms and filter feeds (such as desirable sponges) in a tank. Coals and sponges can directly metabolize acetate. Acetate is one of the highest turnover organic in the ocean. Thus, opting for vinegar can be very natural and is something out tank inhabitants are accustomed to.

What about other carbon sources such as NP Bacto Balance, NOPOX, or Sugar?

You can carbon dose with NP Bacto Balance or NOPOX, but dosing straight vinegar or vodka is cheaper and readily available in stores.

One caveat is dosing sugar. While it was popular to dose sugar in a tank several decades ago, it has largely fallen out of favor. It tends to "brown out" certain corals. I wouldn't consider dosing sugar.

Vodka (80 proof) is eight times more concentrated than 5% Vinegar. Dosing 8 times less vodka than vinegar will equal the pH lowering effect and nitrate reduction.

What kind of vinegar or vodka should I use?

Plain Distilled vinegar (5% acidity) from the grocery store is best. NOT filtered vinegar.

Unflavored 80 proof vodka (40% ethanol) is best.


Instructions and rules to follow when carbon dosing with my charts:

1. Dose during daylight hours. Carbon dosing will reduce pH and oxygen, so it's wise to dose while those parameters are naturally at their highest.

2. Skimming and good surface agitation is strongly encouraged. If you don't have a skimmer, stay on the lower end of the chart, and don't progress unless it's clear the tank is fine. High flow will allow more oxygen in the tank and will gas off the extra CO2 that gets produced.

3. You can dose vodka in one shot (bolus dosing), but vinegar is best spread-out with a dosing pump or manually twice a day.

4. Vinegar and Vodka have the same pH-lowering effect, but vinegar is more upfront, while vodka is all later as it becomes consumed by bacteria. You cannot easily detect the pH drop from vodka, but they are equal when comparing the chart dosages for tank size.

5. You do not need to increase the dose after week 2 if nitrates are reducing earlier.

6. Watch your tank and make observations. Once your nutrients are in line, find a small maintenance dose for your tank. You choose the final dose based on your testing and tank inhabitants.

7. Keep track of nutrients and ensure they don't bottom out. Nitrates won't bottom overnight; you won't wake up on the second day and see 100 ppm turn to 0.00 ppm. It's much more gradual than that.

8. Some people notice cyano issues with vodka than with vinegar. If that is the case, switching to vinegar is a wise choice.

Here are the charts. If you have any questions, feel free to ask.

Thinking of doing this for my tank. Its 1 year old. NO3 is 20 and PO4 is .20. 60 gallon display with 30 gallon sump (total water volume is ~70 gallons). I currently have some GHA and cyano (slowing down since adding more CUC). I beat SCA dinos from March 2024-June 2024. All in all my corals and fish are looking awesome. Should I dose vinegar instead of vodka since I have a little cyano on the sandbed? Hoping to get my nutrients more around NO3 of 10 and PO4 of .1

 

[rishma]

Thinking of doing this for my tank. It’s 1 year old. NO3 is 20 and PO4 is .20. 60 gallon display with 30 gallon sump (total water volume is ~70 gallons). I currently have some GHA and cyano (slowing down since adding more CUC). I beat SCA dinos from March 2024-June 2024. All in all my corals and fish are looking awesome. Should I dose vinegar instead of vodka since I have a little cyano on the sandbed? Hoping to get my nutrients more around NO3 of 10 and PO4 of .1

Yes I’d dose vinegar in your situation. You are not far off with 0.2 and 20, should work well

 

[stewy14]

what's the best brand of vodka to use for this?

 

[Randy Holmes-Farley]

what's the best brand of vodka to use for this?

Whatever is cheapest.

 

[Reefering1]

I use tito's

 

[aquadise]

I might not understand well. So i have a question:

organic + 124 NO3– + 124 H+ → 122 CO2 + 70 N2 + 208 H2O

So far I understand that above formation only happened at anaerobic environment (i meant the step converting directly to N2 like that). I only saw above formation when I read the instruction of Deltec Denitrification Reactor. I assumed the above formation rarely happened in a reef tank, only at special condition, need to be set up by reefer.

Does any other process happen while dosing carbon liquid? I think other type of bacterial can collect the elements N, P, and C (nitrogen, phosphorous and carbon) to form their biomass, then become food for coral, or dead and skimming out by a skimmer.
So if this theory is true, it will reduce phosphate as well.

It also matches with the other theory: "if phosphate is zero, you cannot lower the nitrate level anymore by using only carbon dosing".

I am confused.

 

[Randy Holmes-Farley]

The equation you posted is the standard equation for denitrification. Denitrification as a process does not consume phosphate.

The bacteria doing it require some phosphate, particularly for them to grow in numbers.

I expect denitrification does happen when organic carbon dosing, but there will be a large amount of simple growth and population increase of bacteria and other organisms, and that definitely needs both N and P from some source to take place.

Bacterial growth consumes far more N than P, and most importantly for the observation that P drops little with organic carbon dosing is that there’s a huge reservoir of phosphate bound to rock and sand that will come off any time you try to lower it, effectively trying to hold phosphate where it is.

 

[Miami Reef]

Bacterial growth consumes far more N than P, and most importantly for the observation that P drops little with organic carbon dosing is that there’s a huge reservoir of phosphate bound to rock and sand that will come off any time you try to lower it, effectively trying to hold phosphate where it is.

This.

When using carbon dosing to lower high phosphates, nitrates will likely bottom out without adding nitrate/ammonium.

 

[rishma]

This.

When using carbon dosing to lower high phosphates, nitrates will likely bottom out without adding nitrate/ammonium.

Having been doing carbon dosing for a really really long time, this is always true in my experience. In 1999 I was using vinegar to increase my Kalkwasser concentration…for reasons I didn’t understand for another decade my nitrate would go to zero and my corals would get really pale.

And when I first started carbon dosing on purpose my nitrate would go to zero, I’d dose some nitrate, then my phosphates would plummet. I fought that yo-yo until I gave up on carbon dosing.

Finally when I came back to carbon dosing last year tried to be more disciplined about nutrients added. I would dose a little additional N without P along with food and carbon dosing. I was able to keep things fairly stable. I considered mixing nitrate in my vinegar/vodka but never did it. Tropic Marin concocted their NP-Bacto Balance with this aim, but I guess it also includes some P. It’s not perfect but heading the right direction based on my experience.

 

[coweyes298]

My tank is 90 gallon ish display and 30 ish sump. I have been neglecting to do husbandry since covid and recently measured NO3 with hanna and it's over 75ppm... Started vinegar dosing using this chart, and right now I am in week 2 with 60 ml per day. Started to see measurement to be at 74.8 ppm these two days and hoping it will drop in the following days. I only have a pig blue tang and pair of clown with no coral and the system is about 7 or 8 years old. I feed heavily with pellet and frozen that's why my NO3 is sky high. I started to see film built up at the end of 1 st week of vinegar dose and it's now more pronounce. I am also running GFO in reactor and it brings my PO4 down from 2.5 ppm (yes 2.5!!!) to now at 0.4. I am aiming for NO3 = 10 to 20 and PO4 = 0.1 ~ 0.15.
I don't have much of algae problem in the past 4 or 5 years, only diatom like patches shows up here and there whenever I do water change and vacuum my sand bed recently. (I haven't done water change in the past 4 or 5 years but started tidying up my tank recently with WC and other method....I know I am a very bad tank keeper lol).

 

[Miami Reef]

I only have a pig blue tang and pair of clown with no coral and the system is about 7 or 8 years old. I feed heavily with pellet and frozen that's why my NO3 is sky high.

I don't have much of algae problem in the past 4 or 5 years, only diatom like patches shows up here and there whenever I do water change and vacuum my sand bed recently. (I haven't done water change in the past 4 or 5 years but started tidying up my tank recently with WC and other method....I know I am a very bad tank keeper lol).

Tanks with fish-only can tolerate much higher nutrient levels. It sounds like you’re doing a great job!

 

[surcalation]

Right then gang, I have been dosing Vodka (40%, 80 Proof) now for 4 weeks and need to know what to do for weeks 5 and 6.

Tank is roughly 1000L or 225 Gallons
I test weekly with Salifert NO3 kit and Hanna P04 and DKH. Use a D-D Refractometer for Salinity
For Phosphate I do the 3min Test and then do 5 quick tests straight after.

Week 0:
N03 50ppm
Po4 24ppb (25/21/17/20/20)
Sal 1.024
Alk 6.8dkh

Week 1:
Vodka 7ml per day
N03 50ppm
Po4 31ppb (21/24/28/38/24)
Sal 1.024
Alk 7.5dkh

Week 2:
Vodka 14ml per day
N03 50ppm
Po4 14ppb (13/13/5/5/0)
Sal 1.024
Alk 8dkh

Week 3:
Vodka 21ml per day
N03 50ppm
Po4 27ppb (26/29/28/21/19)
Sal 1.024
Alk 8.6dkh

Week 4:
Ran Rowa Carbon for 4 days then changed my RowaPhos.
Vodka 28ml per day
N03 50ppm
Po4 13ppb (21/14/17/19/21)
Sal 1.024
Alk 8.7dkh

I have been getting white film on my glass every couple of days. Tiny bits of green cyano but not much at all.
During weeks 1-2 I have had the house decorated and the skimmers being going extra skimmy!

Pink streak wrasse and red scooter blenny enjoying all the extra copepods which have come via the white film.

Do I continue at 28ml per day until NO3 comes down?

 

[rc1]

Right then gang, I have been dosing Vodka (40%, 80 Proof) now for 4 weeks and need to know what to do for weeks 5 and 6.

Tank is roughly 1000L or 225 Gallons
I test weekly with Salifert NO3 kit and Hanna P04 and DKH. Use a D-D Refractometer for Salinity
For Phosphate I do the 3min Test and then do 5 quick tests straight after.

Week 0:
N03 50ppm
Po4 24ppb (25/21/17/20/20)
Sal 1.024
Alk 6.8dkh

Week 1:
Vodka 7ml per day
N03 50ppm
Po4 31ppb (21/24/28/38/24)
Sal 1.024
Alk 7.5dkh

Week 2:
Vodka 14ml per day
N03 50ppm
Po4 14ppb (13/13/5/5/0)
Sal 1.024
Alk 8dkh

Week 3:
Vodka 21ml per day
N03 50ppm
Po4 27ppb (26/29/28/21/19)
Sal 1.024
Alk 8.6dkh

Week 4:
Ran Rowa Carbon for 4 days then changed my RowaPhos.
Vodka 28ml per day
N03 50ppm
Po4 13ppb (21/14/17/19/21)
Sal 1.024
Alk 8.7dkh

I have been getting white film on my glass every couple of days. Tiny bits of green cyano but not much at all.
During weeks 1-2 I have had the house decorated and the skimmers being going extra skimmy!

Pink streak wrasse and red scooter blenny enjoying all the extra copepods which have come via the white film.

Do I continue at 28ml per day until NO3 comes down?

I am on week 5 dosing at 200ml white vinegar and like you I have seen no changes on my 225 still over 100+

 

[Reefering1]

It takes time guys. Vodka is 8x more potent than vinegar. So 30ml of vodka is about equivalent to 240ml of Vinegar. If the numbers aren't coming down, you can double the dose next week. If you're seeing some white film or cyano, I probaly wouldn't double it- maybe go to 45ml if I was at 28ml of vodka.

 

[Miami Reef]

I am on week 5 dosing at 200ml white vinegar and like you I have seen no changes on my 225 still over 100+

You should dose some trace elements. Your system appears to be limited, especially with the very weak refugium growth.

Also, Your nitrate kits aren’t very accurate. Saying a value is 100ppm + isn’t helpful because you won’t know if there’s an overall down-trend.

 

[pwfess]

The reasons I'm updating the Vinegar and Vodka dosing charts are two-fold:

1. The ramp was unnecessarily slow. There was no perceived benefit to such a tedious ramp, and it led to reefers quitting because they thought carbon dosing didn't work.

2. The ramp did not scale up correctly at all. A 40x larger tank only received 2x the needed dose. (A 1,000-gallon tank only received twice the dose of a 25-gallon tank).


Carbon dosing is a fantastic way to lower nutrients, more specifically nitrate. The reason is three-fold:

1. Organisms, such as bacteria, contain much more nitrogen than phosphorous.

2. Denitrification is a process that happens in anaerobic conditions (little to no oxygen). These bacteria require an organic to oxidize the nitrate molecule (NO3-) into Nitrogen (N2). They use the oxygen that is attached to the nitrate molecule to respire. Thus, there will be NO phosphate consumed during this process.

Here is the equation by @Randy Holmes-Farley :

organic + 124 NO3– + 124 H+ → 122 CO2 + 70 N2 + 208 H2O

3.We have an immense reservoir of phosphate bound to calcium carbonate rocks and sand. To put to pespective, a 50% water change with nutrient-free water will successfully reduce your nitrate values by 50%. More often than not, the phosphate value will climb right back up near the starting point after a day; PO4 tries to be in constant equilibrium with the bulk water column and calcium carbonate surfaces.


For these reasons, I do NOT recommend dosing carbon solely for controlling phosphates. It is likey to deplete nitrate before seeing phosphate mildly decrease.

What are the benefits of carbon dosing?

Besides reducing nitrate, spurring bacteria is the main benefit. This bacteria can feed many organisms and filter feeds (such as desirable sponges) in a tank. Coals and sponges can directly metabolize acetate. Acetate is one of the highest turnover organic in the ocean. Thus, opting for vinegar can be very natural and is something out tank inhabitants are accustomed to.

What about other carbon sources such as NP Bacto Balance, NOPOX, or Sugar?

You can carbon dose with NP Bacto Balance or NOPOX, but dosing straight vinegar or vodka is cheaper and readily available in stores.

One caveat is dosing sugar. While it was popular to dose sugar in a tank several decades ago, it has largely fallen out of favor. It tends to "brown out" certain corals. I wouldn't consider dosing sugar.

Vodka (80 proof) is eight times more concentrated than 5% Vinegar. Dosing 8 times less vodka than vinegar will equal the pH lowering effect and nitrate reduction.

What kind of vinegar or vodka should I use?

Plain Distilled vinegar (5% acidity) from the grocery store is best. NOT filtered vinegar.

Unflavored 80 proof vodka (40% ethanol) is best.


Instructions and rules to follow when carbon dosing with my charts:

1. Dose during daylight hours. Carbon dosing will reduce pH and oxygen, so it's wise to dose while those parameters are naturally at their highest.

2. Skimming and good surface agitation is strongly encouraged. If you don't have a skimmer, stay on the lower end of the chart, and don't progress unless it's clear the tank is fine. High flow will allow more oxygen in the tank and will gas off the extra CO2 that gets produced.

3. You can dose vodka in one shot (bolus dosing), but vinegar is best spread-out with a dosing pump or manually twice a day.

4. Vinegar and Vodka have the same pH-lowering effect, but vinegar is more upfront, while vodka is all later as it becomes consumed by bacteria. You cannot easily detect the pH drop from vodka, but they are equal when comparing the chart dosages for tank size.

5. You do not need to increase the dose after week 2 if nitrates are reducing earlier.

6. Watch your tank and make observations. Once your nutrients are in line, find a small maintenance dose for your tank. You choose the final dose based on your testing and tank inhabitants.

7. Keep track of nutrients and ensure they don't bottom out. Nitrates won't bottom overnight; you won't wake up on the second day and see 100 ppm turn to 0.00 ppm. It's much more gradual than that.

8. Some people notice cyano issues with vodka than with vinegar. If that is the case, switching to vinegar is a wise choice.

Here are the charts. If you have any questions, feel free to ask.

How would you go about bumping up your pH if it drops with vinegar dosing? I already CO2 scrub to keep it between 8.1-8.4. Im getting readings around 7.9-8.05 with dosing. Thanks.

 

[Miami Reef]

How would you go about bumping up your pH if it drops with vinegar dosing? I already CO2 scrub to keep it between 8.1-8.4. Im getting readings around 7.9-8.05 with dosing. Thanks.

There are a few things I’d do:

Saturate the vinegar with kalkwasser. Add enough kalk powder to the vinegar until there is some precipitation on the bottom. Dose only the clear portion. The precipitation will redissolve as you add more vinegar, so it’s not wasted. This will add some alk to the tank.

Keep alkalinity from 7-11dKH, but I’d prefer it around 9-11 if higher pH is the goal. Higher alk leads to higher pH the CO2 equilibrium changes.

Use sodium hydroxide or kalkwasser as part of your alkalinity additive.

Increase fresh air into the house.

There are some other things you can do, but those are my favorite ways.