vinegar added to kalk top off

[graham hunt]

hi,i was hoping you chemistry guys would help me,i have been adding vinegar to my tank as a carbon source for a while now(350gall,50ml vin. bollus)as clam and coral growth is noticable i have also been adding kalk to top off for the same period(2tsp per gal)i thought it was time to lift cal and kh up to steady out useage i am now adding 3 tsp of kalk and 45ml of vinegar to each gall of ro water as top off,tank evaporates a steady 2.5 gall a day,this seems to have lifted cal,kh and ph slightly and appears steady now.my question is does the vinegar added to kalk get degraded as a carbon source thus i need to carry on bollus vinegar dose in tank or am i effectively now adding usefull carbon via top off?(approx 112ml in 2.5gall of top off slowly over 24hrs)
many thanks for looking.
ps.as posting is rare and difficult due to sight problems but reading is possible if slow via zoom function,i would really like to take this oppertunity to thank you guys for your compleate selfless and patient work on this and other forums frequently a lifesavers,regards graham.

 

[tmz]

The vinegar won't degrade in the fully saturated limewater/kalkwasser ;the basicity and related high pH prevents bacterial growth.

The acidity of undiluted vinegar prevents bacterial growth when not used in a basic solution like limewater which is why it shouldn't be diluted with plain freshwater.

Thanks for your kind words.

 

[graham hunt]

many thanks

many thanks

The vinegar won't degrade in the fully saturated limewater/kalkwasser ;the basicity and related high pH prevents bacterial growth.

The acidity of undiluted vinegar prevents bacterial growth when not used in a basic solution like limewater which is why it shouldn't be diluted with plain freshwater.

Thanks for your kind words.

thank you tom,that has eased my mind,seems to work very well nice slow carbon and calc addition,seems much to easy!
regards graham.

 

[trilinearmipmap]

Has anyone automated a vinegar addition into their kalk dosing system? I have a DIY kalkreactor added to my auto-topoff, I was thinking of adding a dosing pump to add vinegar into the kalkreactor, unless there is a simpler/easier way of doing this.

 

[AquamanE]

I had the same question as Graham but didnt understand a word TMZ said.

 

[Randy Holmes-Farley]

It is trivial to automate vinegar dosing from a still reservoir of limewater (kalkwasser). It is difficult and, IMO, not worth the effort, to try to do it with a limewater reactor.

Eddie: Yes you can mix vinegar into kalkwasser just fine.

 

[tmz]

I had the same question as Graham but didnt understand a word TMZ said.

Vinegar is 95% water and 5% acetic acid with a pH of around 2.4. At that level of acid bacteria don't live and degrade the organic carbon . At significantly greater dilution levels ; they do.
Likewise, limewater/kalk at full saturation has a high pH(around 12.4) which prevents bacteria from degrading the organic carbon.

 

[buildinboats]

Vinegar is 95% water and 5% acetic acid with a pH of around 2.4. At that level of acid bacteria don't live and degrade the organic carbon . At significantly greater dilution levels ; they do.
Likewise, limewater/kalk at full saturation has a high pH(around 12.4) which prevents bacteria from degrading the organic carbon.

Sorry to hijack the post but I was just going to start a thread asking if I could use a Litermeter dosing pump to dose vinegar. I was thinking about diluting the vinegar with RO/DI water to get the interval doses down to a lower concentration of vinegar that would be dosed by the Litermeter. So you are saying there is the possibility of the carbon source being degraded by bacteria in the bottle containing this solution?

 

[tmz]

Sorry to hijack the post but I was just going to start a thread asking if I could use a Litermeter dosing pump to dose vinegar. I was thinking about diluting the vinegar with RO/DI water to get the interval doses down to a lower concentration of vinegar that would be dosed by the Litermeter. So you are saying there is the possibility of the carbon source being degraded by bacteria in the bottle containing this solution?

Yes, exactly. However, I don't know precisely how much below 5% you can go without the bacterial activity.

 

[tmz]

Looked around a little for more information.Here, is one article that suggests optimal pH for some heterotrophic( consumers of organic carbon) thrive at an optimal pH of 7.0 but also grow albiet slowly at pH of 2.8. Since 5% vinegar is around 2.5 pH that wouldn't leave much room for dilution.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC250419/

 

[tmz]

The liter meter pump is a 250ml per minute pump. the liter meter 3 with the built controller can dispense a minimum of 50ml per day to a max of 99 liters per day . How much vinegar do you need to dose . If you need less than 50ml or don't have the controller set up using a 1.1ml peristaltic pump on a timer might be easier.

 

[buildinboats]

The liter meter pump is a 250ml per minute pump. the liter meter 3 with the built controller can dispense a minimum of 50ml per day to a max of 99 liters per day . How much vinegar do you need to dose . If you need less than 50ml or don't have the controller set up using a 1.1ml peristaltic pump on a timer might be easier.

So I would be taking a risk of having bacteria bloom in the solution by diluting the vinegar . I do have a Litermeter 3 and had originally planned on 40 ml per day. If it will do 50 I may be in the ballpark. Thanks for all of the information, I now have a clear route to go after reading your comments.

 

[Randy Holmes-Farley]

There are two risks, the first is minor and the second more significant.

The first risk is not really knowing how much (if any) vinegar you were actually dosing after a period of time.

The second is that as the vinegar is converted into CO2, you will actually deliver CO2 into the limewater where it becomes carbonate and precipitates calcium carbonate. So instead of the vinegar promoting the dissolution of calcium hydroxide, you may find that the solution actually degrades the calcium hydroxide and might even reduce the amount of calcium and alkalinity delivered to the tank.

 

[dirtycontour]

There are two risks, the first is minor and the second more significant.

The first risk is not really knowing how much (if any) vinegar you were actually dosing after a period of time.

The second is that as the vinegar is converted into CO2, you will actually deliver CO2 into the limewater where it becomes carbonate and precipitates calcium carbonate. So instead of the vinegar promoting the dissolution of calcium hydroxide, you may find that the solution actually degrades the calcium hydroxide and might even reduce the amount of calcium and alkalinity delivered to the tank.

Are there any tell tale signs that the vinegar would be reducing the potency of the kalk?

 

[Randy Holmes-Farley]

Reduced alkalinity in the tank, if you monitor that.

Reduced alkalinity in the reactor effluent if it is totally clear (but not if it isn't, since particles of CaCO3 will dissolve in an alk test)..

More solids in the reactor that never dissolve.

 

[dirtycontour]

Sounds good, thanks for the quick reply.

 

[Randy Holmes-Farley]

:thumbsup:

Good luck and let us know how it works out if you try it.

 

[tmz]

So I would be taking a risk of having bacteria bloom in the solution by diluting the vinegar . I do have a Litermeter 3 and had originally planned on 40 ml per day. If it will do 50 I may be in the ballpark. Thanks for all of the information, I now have a clear route to go after reading your comments.

You are welcome.
Yes, and bacterial activity would produce the two risk outcomes Randy described if you are adding it to kalkwasser/limewater. If you are not putting it in limewater the first still applies.

Also,if enough CO2 entered limewater it might drop pH low enough to dissolve precipitated impurities as well as weakening the calcium hydroxide strength..

FWIW, I dose vodka and vinegar but not in the limewater. I use the litermeter 3 for limewater dosing ; I don't need the extra boost of calcium hydroxide in the limewater solution and like keeping the two processes separate but that's just me. I might add a pump to the litermeter 3 for separate organic carbon dosing at some point.

What is the water volume of the aquarium ,sump, refugia etc.; btw?

 

[buildinboats]

There are two risks, the first is minor and the second more significant.

The first risk is not really knowing how much (if any) vinegar you were actually dosing after a period of time.

Couldn't I observe the vinegar reservoir diminishing or if the pump stops dosing, nitrate rising and more frequent cleaning of the front glass?

I might add a pump to the litermeter 3 for separate organic carbon dosing at some point.

What is the water volume of the aquarium ,sump, refugia etc.; btw?

No sump or refugium, 1991 vintage. :headwally: About 140 system gallons, it's a 150.

 

[tmz]

50ml of 5% vinegar should be ok for a 140 gallons. Most settle in somewhere between .4 ml per gallon of water volume to .8ml after amping up over a week or two. Each tank is different though;some use a lot less or tolerate a little more.. I'd start at 20ml per day and run it up to 50ml over a week or two. You can put the litermeter on a timer to run it only during 12 daylight hours which would cut the 50ml minimum per 24 hours to 25ml actually dosed. Then you could add and hour or two per day to the run time to get to 50ml.

Oraganic carbon dosing is best with a skimmer to remove the excess bacteria and the nutrients they hold