I was reading the directions on my kent kalk container (what a concept eh) and it siad that kalk will not raise the ph if added slowly. and last week i was told to use it to raise my ph. So should i just increase my flow of kalk and if so how many drips a second are we talking about. My P.H is like 7.6 and i have no idea how my stuff is still alive!
another question about kalk
- Thread starter brc0488
- Start date
Dr. Farley (chemistry forum) can give you all the in's and out's of using limewater and the resultant pH.
http://www.reefkeeping.com/issues/2004-09/rhf/index.php
http://www.reefkeeping.com/issues/2005-01/rhf/index.php
Those should get you started.
http://www.reefkeeping.com/issues/2004-09/rhf/index.php
http://www.reefkeeping.com/issues/2005-01/rhf/index.php
Those should get you started.
"uch an increase is clearly too large. Adding a smaller portion all at once can, however, be acceptable. Adding, for example, 0.25% of the aquarium volume (0.25 gallons or 1 L of limewater per 100 gallons of aquarium water) will raise the pH by only 0.1 to 0.2 pH units. Unless the pH is high (>8.4) before the addition, that amount is likely acceptable. The other concern with all-at-once dosing is that the local pH in the area of the addition will rise considerably higher than the values above. So dosing must be done far from living organisms, and in high flow areas that will facilitate fast mixture. In some aquaria, such restrictions make all-at-once dosing of limewater prohibitively risky to living organisms."
This is confusing to me...isnt this saying that a large quanity of kalk wont affectr the P.H so if i dose a whole gallon of kalk (kalk and water at 1.5 tsp a gallon) and my ph is at like 7.5-.6 between an 8 hour period how much increase will i aprox. see
This is confusing to me...isnt this saying that a large quanity of kalk wont affectr the P.H so if i dose a whole gallon of kalk (kalk and water at 1.5 tsp a gallon) and my ph is at like 7.5-.6 between an 8 hour period how much increase will i aprox. see
CH
New member
You really shouldn't use Kalk to increase your PH, rather just maintain it. Get a ph buffer that will help you raise it slowly, and then jsut dose the kalk at about 1 to 2 drips per second to maintain.
You could try dripping it a bit faster, but I wouldn't just pour the whole thing in, IMO.
You could try dripping it a bit faster, but I wouldn't just pour the whole thing in, IMO.
mathias999us
New member
Like old salty said, read Dr. Farley's chemistry forum - he's got a bunch of links to articles concerning this topic.
The jist of your question is: Does kalkwasser raise the pH?
Yes and no. Kalkwasser will temporarily raise your pH by introducing hydroxide ions into your tank. This will cause the carbonic acid (and other acids) in the water (disolved CO2 from the atmosphere) to form carbonate ions - hence "removing" carbonic acid. (Note that this is why kalk is a balanced addition, since you end up adding equal parts calcium and carbonate ions to your water) Since carbonic acid and CO2 in the atmosphere maintain an equilibrium, your "C02 deficient" tank water will start drawing in additional CO2 from the air, which will lower the pH back to wher it was. The catch here is that this equilibrium takes some time, which is limited by the rate at which the water can absorb carbon dioxide.
So, kalk will only temporarily raise your pH. It's not used for raising pH, it's used for the balanced addition of calcium and carbonate ions.
Also, contrary to what CH said above, I wouldn't necessarily just throw pH buffer in your tank to correct a pH problem. pH buffer is just buffer - it just raises your alkalinity by introducing more carbonate ions into the water (and hence impacting the carbonic acid/C02 equilibrium between the water and air), and it will skew your calcium/carbonate ion balance in your tank (assuming the balance is correct right now).
Depressed pH is more of a symptom of high C02 levels in the air where the tank is being used (or an incorrectly adjusted CO2 reactor). If you have a lot of gas appliances, or your house is stuffy because it's closed up in the winter, this can be a huge contributing factor.
Hope this helps,
Mathias
The jist of your question is: Does kalkwasser raise the pH?
Yes and no. Kalkwasser will temporarily raise your pH by introducing hydroxide ions into your tank. This will cause the carbonic acid (and other acids) in the water (disolved CO2 from the atmosphere) to form carbonate ions - hence "removing" carbonic acid. (Note that this is why kalk is a balanced addition, since you end up adding equal parts calcium and carbonate ions to your water) Since carbonic acid and CO2 in the atmosphere maintain an equilibrium, your "C02 deficient" tank water will start drawing in additional CO2 from the air, which will lower the pH back to wher it was. The catch here is that this equilibrium takes some time, which is limited by the rate at which the water can absorb carbon dioxide.
So, kalk will only temporarily raise your pH. It's not used for raising pH, it's used for the balanced addition of calcium and carbonate ions.
Also, contrary to what CH said above, I wouldn't necessarily just throw pH buffer in your tank to correct a pH problem. pH buffer is just buffer - it just raises your alkalinity by introducing more carbonate ions into the water (and hence impacting the carbonic acid/C02 equilibrium between the water and air), and it will skew your calcium/carbonate ion balance in your tank (assuming the balance is correct right now).
Depressed pH is more of a symptom of high C02 levels in the air where the tank is being used (or an incorrectly adjusted CO2 reactor). If you have a lot of gas appliances, or your house is stuffy because it's closed up in the winter, this can be a huge contributing factor.
Hope this helps,
Mathias
and thanks mathias that was helpfull. the only thinig im confused about was that Randy Holmes (sorry if i spelled in wrong) told me to use kalk to raise my P.H. Does the size of the house have anything to do with concentration of CO2 casue i live in a fairly decent sized house and the room with tank has a fan that is constenly running i dont know if this contributes to the concentration of C02 but i thought i would throw that info out in the air.
LobsterOfJustice
Recovering Detritophobe
In my case kalk has raised and maintained my pH. Used to run right around 8, now I have kalk in my topoff water and i run around 8.3.
mathias999us
New member
brc - Well, I think the idea that Randy Holmes was leading you towards, and also what LobsterOfJustice is experiencing here, is that if you are consistenly applying kalk to your tank for all of your top off needs, then you will constantly be shifting the carbonic acid/CO2 equilibrium, resulting in a prolonged pH shift, for the duration of time you continue to add kalk for all of your topoff. So, perhaps I misunderstood your question, but kalk is not meant to be used like a one time correction - you will have to continue to use it as long as you want to counteract your pH problem. Lobster of Justice - if you stopped using kalk for your topoff, I think you'd probably find that your pH would return to the ~8.0 range it was at before and probably rather quickly...
That being said, IMO it's an EXCELLENT way to combat high CO2 problems, which it sounds like you may have. I don't think we can draw a specific conclusion about the size of your house, impacting the CO2 levels, only to say that the bigger the volume, the more diluted the CO2 will be. However, you may have more carbon-dioxide producing appliances, people, pets, etc than the average smaller house. And this would all dependent on the rate of exchange with the air outside your house as well. (leaky windows, open windows, etc).
I have the same depressed pH problems as well. I'm gas appliances too, and we don't open up a lot. It seems like it's either too hot, or too cold here. I live east of Los Angeles, so presumably the CO2 concentraition in the air around my city is higher than average also.
I ran a vinyl hose from the outside of my house roof, through the attic, and hooked it to my skimmer air intake to try to combat some of the elevated CO2 levels in my house, with some success, probably on average around +0.1-0.2 pH. And I started using kalk for all my top off water, which made the biggest difference. Of course, it needs to be monitored, as there are no controlls on how high the pH will go except the amount you add to it. For most people, a solution of saturated kalkwasser roughly matches an appropriate dose for the amount of evap that occurs in their tank. In my 135, that was the case, and it worked perfectly. I'm using kalk in my nano auto-topoff now, and the evap has been much slower, so the pH (and KH/Calc level) improvement has not been nearly as noticeable.
I think for you, I'd be thinking about that well water. You're adding water with unknown quatites/types of disolved gases and other minerals... personally, I would not use anything other than RO/DI or distilled water in my tank (although, kalk does have some self-purifying properties, such as the precipitation of phosphates and other heavy metals).
Hope that helps,
Mathias
That being said, IMO it's an EXCELLENT way to combat high CO2 problems, which it sounds like you may have. I don't think we can draw a specific conclusion about the size of your house, impacting the CO2 levels, only to say that the bigger the volume, the more diluted the CO2 will be. However, you may have more carbon-dioxide producing appliances, people, pets, etc than the average smaller house. And this would all dependent on the rate of exchange with the air outside your house as well. (leaky windows, open windows, etc).
I have the same depressed pH problems as well. I'm gas appliances too, and we don't open up a lot. It seems like it's either too hot, or too cold here. I live east of Los Angeles, so presumably the CO2 concentraition in the air around my city is higher than average also.
I ran a vinyl hose from the outside of my house roof, through the attic, and hooked it to my skimmer air intake to try to combat some of the elevated CO2 levels in my house, with some success, probably on average around +0.1-0.2 pH. And I started using kalk for all my top off water, which made the biggest difference. Of course, it needs to be monitored, as there are no controlls on how high the pH will go except the amount you add to it. For most people, a solution of saturated kalkwasser roughly matches an appropriate dose for the amount of evap that occurs in their tank. In my 135, that was the case, and it worked perfectly. I'm using kalk in my nano auto-topoff now, and the evap has been much slower, so the pH (and KH/Calc level) improvement has not been nearly as noticeable.
I think for you, I'd be thinking about that well water. You're adding water with unknown quatites/types of disolved gases and other minerals... personally, I would not use anything other than RO/DI or distilled water in my tank (although, kalk does have some self-purifying properties, such as the precipitation of phosphates and other heavy metals).
Hope that helps,
Mathias
yea i just got an ro unit just finding time to set it up...also i had to wait on some fittings that had cracked in transit thank you mathias for your help... so if the hose from the outside only brought your P.H up around .1-.2 than its probally not worth convincing my mom to let me run a tube outside the house eh?
mathias999us
New member
Yeah, it sounds like the main source of your problem is that untreated well water....
Billybeau1
Premium Member
Everyones tank is different. What I did was figure my evaporation rate (about a gallon per day) and replaced all top off water with limewater mixed at saturation (2 tsp per gallon). This raised my Ph too much so I cut back on the amount of kalk I mixed in the water until I got the right balance to match evaporation. For me this currently ends up being 1 tsp kalk per gallon. Maintains my Ph at a constant 8.2 and calcium and alk are pretty stable. Keep in mind that you may still need to supplement calcium and alk every now and then. Also in my case, the Midwest, my evaporation rate changes from winter to summer so my formula has to be adjusted as well.
I love limewater
I love limewater
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