OP
OP
geeks. :biggrin:
Why is there hesitancy in using vinegar with Kalk? (1 Viewer)
- Thread starter wolmutt
- Start date
Would vinegar be effective at increasing Kalk potency by adding it to top off water and then running through a kalk reactor? I know it works as a carbon source.
OP
OP
I can't see any reason why that wouldn't work, but I would check with Grigor in case I am missing a factor in my thinking. Personally, I would just take the kalk reactor off line and mix my kalk and vinegar in the same holding container and feed it to the main tank with a dosing pump.
I'm not worried about any negative affects of doing it that way but just wondering if it is affective or not. With my new evaporating fams installed I just increased my top off from 2.5 gallons to about 4 gallons a day. And I dont want to be mixing top off every couple of days to keep up. I just dont have that kind of time right now. besides I got a great deal on my Kalk reactor and have it controlled by my AC Jr. and a float valve as back up.
I have actually been contemplating dumping my CA RX to go with automated 2 part though.
OP
OP
nice. I bet with all that evaporation you will be able to meet your systems demands with more kalk than anything since you are thinking about doing the kalk and vinegar method. With the ph of kalk lowered by the vinegar the next limiting factor is your evaporation rate. I need to get some fans soon. What kind are you using? Anything special?
To a lesser extent, yes, but the most effective way to use kalk and vinegar is via the slurry method....
I have a panel of 9 3" case fans all mounted and wired together running off a 12v power supply. I estimate at least 270 cfm. I cant find any specs on the fans and am guessing they move at least 25cfm each.
As in all mixed in a reservoir and dosed using a dosing pump?
Yes, or you could do a one time dose if you want (depending on your demand too)....
No. This comes up quite frequently in the Chemestry forum on RC. You don't get the same effect. Bacteria can break down the vinegar BEFORE It gets to your Kalk reactor. Reason why it doesn't with the big ole' bucket method is because the high PH of the Kalk/vinegar solution the bacteria cannot survive. So leaving it in your RO resevoir for days before being feed to your Kalk reactor will actually be a detriment not a benefit because as the bacteria metabolize the vinegar CO2 is a by product. Adding additional CO2 to a Kalk reactor will lessen the potency not add to it.
It may be somewhat effective if you did small amounts at a time to last only a day or two but if you do that you might as well dump the reactor altogether because of the added work. Or if you added more complexity by dosing the vinegar at the same time as the Ro but from sepeerate containers. Doing so adds much more complexity that again your better off getting rid of the Kalk reactor altogether and just going with the big ole' bucket method.
Second, adding vinegar to your kalk only works if you have enough kalk. Most people with reactors don't add enough and often enough to actually be fully saturated to begin with. Still want to go with the 2 teapsoon rule. If you add Kalk once a week for example you need to ensure your adding enough to at least = two teaspoons based on your evap. rate. I've said it many many times but conductivity meter is the best way to know when to add more kalk to your reactor.
Honestly, I'd make sure your truly saturated before ever trying vinegar. You may be quite surprised just how much CA/Alk Kalk can really provide when you have a way to measure.
Last edited:
OP
OP
the information age is so cool.
Update:
Saturday I filled up the 5-gallon top off with RO/DI, 10 tsp of kalk and 70 mL of vinegar. I also checked all parameters and added a little two part to get them at 450/9.4/1450 (ca/alk/mg). Those were the levels after I added then rechecked a few hours later.
Today, top off is about to run out, so I rechecked levels. Haven't added any two part over the past few days. Levels were 430 & 6.1 (didn't check mg). pH was also at 8.10 vs. 8.5 as it has been logged the days before the vinegar.
My question, why is the alk off by that much? Should I add more vinegar this time around? When I add more vinegar, can I add more kalk too?
Thanks for everyones help with getting this figured out.
Saturday I filled up the 5-gallon top off with RO/DI, 10 tsp of kalk and 70 mL of vinegar. I also checked all parameters and added a little two part to get them at 450/9.4/1450 (ca/alk/mg). Those were the levels after I added then rechecked a few hours later.
Today, top off is about to run out, so I rechecked levels. Haven't added any two part over the past few days. Levels were 430 & 6.1 (didn't check mg). pH was also at 8.10 vs. 8.5 as it has been logged the days before the vinegar.
My question, why is the alk off by that much? Should I add more vinegar this time around? When I add more vinegar, can I add more kalk too?
Thanks for everyones help with getting this figured out.
it always seemed to me like using acetic acid would deplete the capacity of Ca(OH)2 to provide alkalinity by the rxn
Ca(OH)2 +2 CH3COOH --> Ca2+ + 2H20 + CH3COO-
giving you more Ca than alk. I noticed before when I tried vinegar with kalk that I was having to supplement alk frequently and this was what popped into my head. acetic acid is a weak acid, so it wouldn't normally dissociate, but kalk is a strong base, so it seems like it'd overpower it.
Ca(OH)2 +2 CH3COOH --> Ca2+ + 2H20 + CH3COO-
giving you more Ca than alk. I noticed before when I tried vinegar with kalk that I was having to supplement alk frequently and this was what popped into my head. acetic acid is a weak acid, so it wouldn't normally dissociate, but kalk is a strong base, so it seems like it'd overpower it.
OP
OP
This is interesting. I know in sprungs book he says this method gives you more Ca, but he doesn't say anything about Alk from what I can remember.
depends on what you want to get. I never had a problem keeping Ca high, so I stopped using vinegar. Maybe it is cheaper to supplement alk, also you can use baking soda or soda ash depending on what you want your pH to do.
What I "want" is to have my alk ~ 9, cal ~450, mg ~ 1450 and my pH around 8.3. I also want to have a means of doing this without daily additions of two parts....
May seem kinda unrealistic, but I think that's why we started this discussion to figure out if it could be done without daily additions of two-part. DG was able to get his saturation levels to the point where he didn't need two-part and wasn't experiencing pH swings. I wasn't able to get the appropriate ca/alk demands and I was/am having trouble keeping my pH at a little safer levels. So that's the goal, just trying to have an open discussion to figure out if it can be realized.
May seem kinda unrealistic, but I think that's why we started this discussion to figure out if it could be done without daily additions of two-part. DG was able to get his saturation levels to the point where he didn't need two-part and wasn't experiencing pH swings. I wasn't able to get the appropriate ca/alk demands and I was/am having trouble keeping my pH at a little safer levels. So that's the goal, just trying to have an open discussion to figure out if it can be realized.
do you buffer your w/c? I would add baking soda, not soda ash when doing so to depress the pH a little bit, and then just do saturated kalk and adjust when necessary. You could also inject CO2 straight into the tank with a pH controller, like a freshwater planted setup to keep your pH where ever you want, and have fans running to get you more evap for more kalk into the tank. just a thought.
I'm not having any low alk issues and been using Kalk only for going on 4 weeks now. Don't forget when the bacteria metabolize the vinegar the result increases alk. So while looking at equations it may look like alk will fall, it doesn't.....