Vodka any better than ethanol?

[Formulator]

I’m a retired professional drinker and don’t want to keep booze in the house for fear of injury… Is there any reason I can’t get the same carbon dosing results from reagent grade ethanol rather than vodka? I can’t think of any, but wanted to ask in case there is some kind of vodka voodoo I’m missing.

 

[crazyfishmom]

I’m a retired professional drinker and don’t want to keep booze in the house for fear of injury… Is there any reason I can’t get the same carbon dosing results from reagent grade ethanol rather than vodka? I can’t think of any, but wanted to ask in case there is some kind of vodka voodoo I’m missing.

I’ve considered some 200 proof molecular grade. My one concern with reagent grade would be some of the byproducts from the industrial processes but molecular grade should be pretty good.

 

[Formulator]

I’ve considered some 200 proof molecular grade. My one concern with reagent grade would be some of the byproducts from the industrial processes but molecular grade should be pretty good.

Isn’t it ironic that hillbilly moonshiners can make purer ethanol in the backwoods of the Appalachian’s than scientists can with industrial scale resources?

 

[crazyfishmom]

Isn’t it ironic that hillbilly moonshiners can make purer ethanol in the backwoods of the Appalachian’s than scientists can with industrial scale resources?

Just a little bit… just a little bit.

More art than science really… just like reefing itself.

 

[Miami Reef]

I’m a retired professional drinker and don’t want to keep booze in the house for fear of injury… Is there any reason I can’t get the same carbon dosing results from reagent grade ethanol rather than vodka? I can’t think of any, but wanted to ask in case there is some kind of vodka voodoo I’m missing.

Vinegar (acetate when added to the aquarium) has a very similar carbon dosing effect as vodka; corals and sponges can directly consume the acetate, which is an added benefit.

 

[Slocke]

Vinegar (acetate when added to the aquarium) has a very similar carbon dosing effect as vodka; corals and sponges can directly consume the acetate, which is an added benefit.

Isn't the acidity an issue?


Would ethanol with a bit of methanol work? Or is methanol dangerous to add? I know that is what is sold to classrooms to stop kids and teachers from drinking it. It does seem a bit counterintuitive, though adding a far more dangerous chemical to stop people from drinking the less dangerous poison.

 

[Formulator]

Vinegar (acetate when added to the aquarium) has a very similar carbon dosing effect as vodka; corals and sponges can directly consume the acetate, which is an added benefit.

I was considering vinegar and had some success with it years ago, but I was reading about nopox being a mixture of the two and thought I might try to emulate that formulation rather than paying the obscene mark-up to Red Sea.

Do you know the science behind why they include both acetic acid and ethanol? Maybe its not really backed by any and in that case I will go back to vinegar.

 

[Miami Reef]

Isn't the acidity an issue?

Vinegar and vodka have identical CO2 released (pH reduction) when dosed on a carbon-molecule basis (vodka is 8x more potent).

The only difference is that vinegar reduces the pH more upfront, while vodka releases CO2 later. The ethanol releases CO2 gradually as bacteria consume it, so it might be harder to detect with aeration, but the total CO2 released is equal.

Spreading vinegar with a dosing pump is an option if you’d like.

but I was reading about nopox being a mixture of the two and thought I might try to emulate that formulation rather than paying the obscene mark-up to Red Sea.

In my opinion, no reason to mix the two. There isn’t a difference when it comes to spurring bacteria or lowering nitrate.

 

[crazyfishmom]

I was considering vinegar and had some success with it years ago, but I was reading about nopox being a mixture of the two and thought I might try to emulate that formulation rather than paying the obscene mark-up to Red Sea.

Do you know the science behind why they include both acetic acid and ethanol? Maybe its not really backed by any and in that case I will go back to vinegar.

They are differentially processed by different strains of bacteria.

 

[Miami Reef]

Would ethanol with a bit of methanol work? Or is methanol dangerous to add?

It is mostly ethanol (as in vodka) and acetic acid (as in vinegar). It contains much smaller amounts of isopropanol and methanol, which I believe are there to prevent drinking and taxation (e.g., they denature it).

I don’t see the need for adding methanol. It may be fine. I don’t have more info on that.

 

[Miami Reef]

They are differentially processed by different strains of bacteria.

Vinegar (acetate) is one of the most processed organic substances in the ocean; most organisms use it. I think that’s the better option for that purpose.

I’m not a believer in needing to grow specific strains of bacteria. I think it’s vastly unimportant with little to no evidence of benefits in reef aquariums.

If you have issues with dinos or cyano with a specific carbon source, switching to another would be a fine solution.

 

[crazyfishmom]

Vinegar (acetate) is one of the most processed organic substances in the ocean; most organisms use it. I think that’s the better option for that purpose.

I’m not a believer in needing to grow specific strains of bacteria. I think it’s vastly unimportant with little to no evidence of benefit in reef aquariums.

I agree that it doesn’t matter for the purposes of nutrient control but they do affect different bacterial strains differentially.

Something that does tend to happen in tanks that heavily rely on carbon dosing is a reduction in the variety of the microbiome toward the outgrowth of particular bacterial strains which could potentially affect a lot downstream. Perhaps having both carbon sources would help support more bacterial strains. Maybe not. I try to keep a relatively open mind about all these things.

 

[Formulator]

Thanks for all the great info! I’m thinking vinegar is the way to go again as it seems the benefit of having both is probably minimal or at least speculative. It really took my last reef to a new level of growth, so I’m hoping this tank will respond in a similar fashion.

Last time I used carbon dosing primarily as a nutrient export method, but my nutrients in this tank are in a pretty good state, so I’m mostly doing it to propagate the bacteria as coral food and will likely need to set-up a nitrate and phosphate dosing scheme to keep things stable. I’ve got an old jebao 4 head dosing pump collecting dust… maybe that’s the real reason

 

[Slocke]

Vinegar and vodka have identical CO2 released (pH reduction) when dosed on a carbon-molecule basis (vodka is 8x more potent).

The only difference is that vinegar reduces the pH more upfront, while vodka releases CO2 later. The ethanol releases CO2 gradually as bacteria consume it, so it might be harder to detect with aeration, but the total CO2 released is equal.

Spreading vinegar with a dosing pump is an option if you’d like.

In my opinion, no reason to mix the two. There isn’t a difference when it comes to spurring bacteria or lowering nitrate.

Are you trying to claim that adding an acid doesn’t reduce pH? Ethanol is almost neutral but acetic acid is well an acid? Yes they are consumed and produce CO2 (and CO2 reacts to form carbonic acid in water) as a byproduct but I doubt that would affect pH all that much. However adding an acid to a tank? I mean acetic acid is a stronger acid then the carbonic acid the CO2 forms in water.

Edit: sorry I’m just confused. I see something’s online that back you up and some that say vinegar does lower the pH in the long term while vodka doesn’t. But I found nothing that explains the first other then what Miami said.

 

[Formulator]

Are you trying to claim that adding an acid doesn’t reduce pH? Ethanol is almost neutral but acetic acid is well an acid?? Yes they are consumed and produce CO2 (and CO2 reacts to form carbonic acid in water) as a byproduct but I doubt that would affect pH all that much. However adding an acid to a tank? I mean acetic acid is a stronger acid then the carbonic acid the CO2 forms in water.

I think he mentioned the pH reduction up-front with vinegar. You guys can hash that one out, but IME the small amount of acid is not enough to affect my pH to an extent that I care. My tank runs about 8.1, so I can afford a slight drop. With auto dosing throughout the day I think I was only dosing like 6 mL at a time to a 120g tank last time.

 

[Miami Reef]

Are you trying to claim that adding an acid doesn’t reduce pH? Ethanol is almost neutral but acetic acid is well an acid? Yes they are consumed and produce CO2 (and CO2 reacts to form carbonic acid in water) as a byproduct but I doubt that would affect pH all that much. However adding an acid to a tank? I mean acetic acid is a stronger acid then the carbonic acid the CO2 forms in water.

The overall pH drop in a closed system should be the same for vinegar and vodka metabolism since the same amount of CO2 is formed from each singe molecule, but vinegar has it drop immediately (from dissociation of the acetic acid) and less later (from production of CO2), while vodka has it all spread out later (making many folks not even notice it).

CH3CH2OH (vodka) + 3O2 --> 2CO2 + 3H2O

CH3CO2H (vinegar) + 2O2 --> 2CO2 + 2H2O

Shouldn’t the vinegar pH drop be double the vodka? The vinegar itself contains H, and the bacteria release CO2 while they consume it?

If we rewrite the vinegar equation in steps, we see that while the H+ release instantly drops pH, the subsequent conversion of the acetate to CO2 only produces half the amount of CO2:

CH3CO2H --> H+ + CH3CO2- (that lowers pH instantly by one H+ per acetic acid))

then we oxidize the acetate:

CH3CO2- + 2O2 --> 1CO2 + 1 HCO3- + 1 H2O

That oxidation has only one CO2 added, instead of 2. The HCO3- does not have much effect on pH since it mostly stays as bicarbonate.

Thus, half of the vinegar pH drop is shown instantly, and about half is shown later when CO2 is made, while vodka does it all later.

 

[Slocke]

I’m not saying you’re wrong it’s just breaking my poor brain
Like if 40% ethanol is about 7 pH and and 5% acetic acid is 2.5pH. How can adding a lot more water suddenly make them the same pH??

I mean the equations do make sense. Does make me realize that carbon dosing is just making CO2. I’m a terrible environmentalist.

 

[Slocke]

Uggh
Thanks @Miami Reef I’ll have my chemist explain it to me very slowly like the fool I am tomorrow.

 

[Randy Holmes-Farley]

I’m a retired professional drinker and don’t want to keep booze in the house for fear of injury… Is there any reason I can’t get the same carbon dosing results from reagent grade ethanol rather than vodka? I can’t think of any, but wanted to ask in case there is some kind of vodka voodoo I’m missing.

I found that in my system, vodka was more likely to cause cyano and used just vinegar .

 

[Randy Holmes-Farley]

Uggh
Thanks @Miami Reef I’ll have my chemist explain it to me very slowly like the fool I am tomorrow.

It has to do with the fact that the vinegar pH drop happens instantly on dosing and is apparent to everyone while the vodka pH lowering is spread out over many hours, but at the end of the day to overall pH effect is nearly identical since the end products (CO2 and water) are exactly identical.

If vinegar dosing itself is spread out, one is likely to observe very similar pH profiles, but if you do once a day dosing, vinegar will give a lower pH during the spike downward.