vodka dilution for doser

Charles Silva · Jul 8, 2017

Hello all

My tank has 1000 liters (net) and I will start dosing 1 mL vodka/day.
Unfortunately my DIY peristaltic pump can only handle 65 mL/min and it hasn´t a potentiometer do adjust the flow.
So the only way is doing a dilution...
Can I prepare the carbon solution (dilution 65 mL RO water + 1 mL vodka) or will bacteria grow in my solution?
Any recomendation how to avoid the alcohol evaporation in my dosing container ?
Can I use a 2 liters transparent container ?

regards,
Charles Silva

Randy Holmes-Farley · Jul 9, 2017

My concern is bacteria will grow. We know from wine and beer that microorganisms can grow in them at 0% alcohol, so something higher than that is needed.

Lightly covering the dosing reservoir should adequately prevent evaporation

Donovan Joannes · Jul 9, 2017

Boiling RODI for a few minutes might help. Cover it up after boiling and leave it to cool before using.

madweazl · Jul 9, 2017

Is 1ml enough to have any affect in 1000 liters of water?

Scott.h · Jul 9, 2017

Buy a different doser?

Randy Holmes-Farley · Jul 10, 2017

madweazl said:
Is 1ml enough to have any affect in 1000 liters of water?

1 mL once a day? I doubt you'll notice the effects, but there will be some.

chipmunkofdoom2 · Jul 10, 2017

Why not dose vinegar instead of vodka? Because most vinegar is 5% acetic acid and vodka is usually 80 proof (40%), vinegar has only about 1/8th the organic carbon. This means you would need to dose 8 times more vinegar than vodka to get the same result. This would allow you to dose much more vinegar than you can dose vodka, and may mean you don't need to dilute the solution at all.

Cory · Jul 19, 2017

chipmunkofdoom2 said:
Why not dose vinegar instead of vodka? Because most vinegar is 5% acetic acid and vodka is usually 80 proof (40%), vinegar has only about 1/8th the organic carbon. This means you would need to dose 8 times more vinegar than vodka to get the same result. This would allow you to dose much more vinegar than you can dose vodka, and may mean you don't need to dilute the solution at all.

Ive thought about this too, but vodka apparently doesnt affect ph while vinegar does.

Vinegar doesn't evaporate and vodka does. So its like a balancing act.

Randy Holmes-Farley · Jul 19, 2017

Cory said:
Ive thought about this too, but vodka apparently doesnt affect ph while vinegar does.

Vinegar doesn't evaporate and vodka does. So its like a balancing act.

It will lower the pH about the same overall, but it does it more when first added and less later (when converted into CO2).

So spread out dosing of each should have about the same pH effects.

Cory · Jul 20, 2017

Randy Holmes-Farley said:
It will lower the pH about the same overall, but it does it more when first added and less later (when converted into CO2).

So spread out dosing of each should have about the same pH effects.

Does vodka lower ph instantly or by bacterial action making co2? Im dosing my vodka 24 times a day via my doser.