Alaskan Reefer
New member
+1 for limewater dosed directly from a settled reservoir. I don't know why a reactor is worth the money unless you just don't have room for a trash can.
Mrs Wages Pickling lime
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Anemonebuff
New member
It adds Ca and Alk as to maintain it. This too will keep your pH up.
Alaskan Reefer
New member
For my tank, it's successfully keeping my Ca at 540, Alk at 8, and pH at 8.3 24/7 -- basically my mixed up Oceanic water doesn't ever budge off those initial numbers, the kalk (limewater) keeps them pegged right there. All this while topping off the water as well. An ATO system with kalk is once of the best things you can do for yourself and your tank.
Alaskan Reefer
New member
You should test for Ca/Alk/pH as you normally would, but don't be surprised if they never move. Specifically important also is Mg, since limewater doesn't help there, and Mg is important to keeping the other three stable. My tank supplements are kalk and the occasional shot of Mg.
You can overdo it if you have sand in the tank -- excess kalk can cause your sand to solidify. In a bare bottom tank, I'm not sure how you can use too much -- all I've seen in mine while knowingly putting in stronger kalk than necessary at the moment is some flaky / crusty accumulation in my sump, which I just remove.
2 tsp per gallon is fully saturated, and you can supersaturate it by adding vinegar if your tank demands it. Start with 1/2 tsp per gallon on your first batch, see if it keeps your Ca/Alk levels steady, and if not move to 1 tsp and so on. In my bare bottom tank, I have just used fully saturated from day one, and my Ca/Alk levels have not budged off of 540/8 since making the transition to BB.
You can overdo it if you have sand in the tank -- excess kalk can cause your sand to solidify. In a bare bottom tank, I'm not sure how you can use too much -- all I've seen in mine while knowingly putting in stronger kalk than necessary at the moment is some flaky / crusty accumulation in my sump, which I just remove.
2 tsp per gallon is fully saturated, and you can supersaturate it by adding vinegar if your tank demands it. Start with 1/2 tsp per gallon on your first batch, see if it keeps your Ca/Alk levels steady, and if not move to 1 tsp and so on. In my bare bottom tank, I have just used fully saturated from day one, and my Ca/Alk levels have not budged off of 540/8 since making the transition to BB.
ser_renely
Active member
how much vinegar do you add?
I discuss the vinegar option here:
What Your Grandmother Never Told You About Lime
http://reefkeeping.com/issues/2005-01/rhf/index.htm
from it:
http://www.reefkeeping.com/issues/2005-01/rhf/index.php#6
Vinegar And Limewater To Reduce pH
The reason that limewater raises the pH of aquarium water so considerably is because of the hydroxide that it adds. As described above, the hydroxide can combine with carbon dioxide to form bicarbonate and bring the pH back down. In many aquaria, however, the aeration is not great enough to bring in carbon dioxide fast enough to meet all this demand, and the pH rises. There are several ways to add additional carbon dioxide to meet this demand, including delivery from a carbon dioxide cylinder. Many aquarists, however, choose to add carbon dioxide in the form of vinegar. Many of them choose to add the vinegar directly to the limewater, although if pH reduction is the goal, it can also be added directly to a high flow area of the aquarium.
When vinegar is added directly to aquarium water, the active ingredient is acetic acid. The first thing it does is ionize into acetate and H+:
6. CH3COOH ---> CH3COO- + H+
Bacteria can then metabolize the acetate to gain energy in the reaction shown below:
7. CH3COO- + 2O2 ----> 2CO2 + H2O + OH-
On balance, the H+ released in (6) and the OH- released in (7) offset each other, and the net addition is simply carbon dioxide:
8. H+ + OH- ----> H2O
9. CH3COOH + 2O2 ----> 2CO2 + 2 H2O
One of the potential side effects of this metabolism is that the bacteria performing the transformation may grow faster because of it. This growth may have positive or negative outcomes. One potentially positive outcome is that as they grow, they will necessarily consume nitrogen and phosphorus, possibly lowering nitrate and phosphate levels in the aquarium. Another is that the bacteria may be a suitable food source for other organisms.
Potential drawbacks can include reduced oxygen as the bacteria use it to consume the acetate, and the appearance of unattractive bacterial mats in the aquarium (reported by some, but not by the majority of vinegar users).
Vinegar And Limewater To Boost Limewater Potency
Another potentially useful attribute of vinegar is that it can be used to help dissolve additional solid lime into limewater. It does this by reducing the hydroxide concentration in the limewater:
10. CH3OOH ----> CH3COO- + H+
The H+ combines with OH- in the limewater:
11. H+ + OH- ----> H2O
The actual dissolution of Ca(OH)2 is limited by the multiplication product of the calcium and hydroxide concentrations in the limewater as shown below:
12. Ca(OH)2 ----> Ca++ + 2OH-
13. [Ca++] x [OH-] x [OH-] <= 5.5 x 10-6
where [Ca++] is the concentration of calcium (in moles/L) and [OH-] is the concentration of hydroxide (in moles/L). Consequently, if you reduce the concentration of OH- via equations (10) and (11), then more Ca(OH)2 can dissolve into solution and still meet the equation (13) requirement.
This would seem like a concern, however, since losing OH- might reduce the amount of alkalinity delivered by the limewater. Luckily, this is not the case. While the OH- is temporarily reduced by the acetic acid in the vinegar, when bacteria metabolize the acetate, they release it back to the water:
14. CH3COO- + 2O2 ----> 2CO2 + H2O + OH-
Consequently, additional solid lime can be dissolved into limewater using vinegar.
How much can be used? The more vinegar that is used, the lower the pH of both the limewater and the aquarium will be. One reasonable point to shoot for is to add about the same amount of total CO2 via the vinegar as is needed by the lime to form HCO3-. This balance is roughly matched by using three level teaspoons of solid lime per gallon of limewater, and 45 ml of vinegar per gallon of limewater. For those aquarists choosing to use vinegar in limewater, these values are a suitable starting point. Note that the pH of the limewater is still quite high, so slow dosing is usually required.
What kind of vinegar should be used? Luckily, cheap distilled white vinegar is likely the best. More expensive flavored and colored vinegars, such as red wine vinegar, will deliver other unnecessary organic molecules to the aquarium, and are best avoided.
What Your Grandmother Never Told You About Lime
http://reefkeeping.com/issues/2005-01/rhf/index.htm
from it:
http://www.reefkeeping.com/issues/2005-01/rhf/index.php#6
Vinegar And Limewater To Reduce pH
The reason that limewater raises the pH of aquarium water so considerably is because of the hydroxide that it adds. As described above, the hydroxide can combine with carbon dioxide to form bicarbonate and bring the pH back down. In many aquaria, however, the aeration is not great enough to bring in carbon dioxide fast enough to meet all this demand, and the pH rises. There are several ways to add additional carbon dioxide to meet this demand, including delivery from a carbon dioxide cylinder. Many aquarists, however, choose to add carbon dioxide in the form of vinegar. Many of them choose to add the vinegar directly to the limewater, although if pH reduction is the goal, it can also be added directly to a high flow area of the aquarium.
When vinegar is added directly to aquarium water, the active ingredient is acetic acid. The first thing it does is ionize into acetate and H+:
6. CH3COOH ---> CH3COO- + H+
Bacteria can then metabolize the acetate to gain energy in the reaction shown below:
7. CH3COO- + 2O2 ----> 2CO2 + H2O + OH-
On balance, the H+ released in (6) and the OH- released in (7) offset each other, and the net addition is simply carbon dioxide:
8. H+ + OH- ----> H2O
9. CH3COOH + 2O2 ----> 2CO2 + 2 H2O
One of the potential side effects of this metabolism is that the bacteria performing the transformation may grow faster because of it. This growth may have positive or negative outcomes. One potentially positive outcome is that as they grow, they will necessarily consume nitrogen and phosphorus, possibly lowering nitrate and phosphate levels in the aquarium. Another is that the bacteria may be a suitable food source for other organisms.
Potential drawbacks can include reduced oxygen as the bacteria use it to consume the acetate, and the appearance of unattractive bacterial mats in the aquarium (reported by some, but not by the majority of vinegar users).
Vinegar And Limewater To Boost Limewater Potency
Another potentially useful attribute of vinegar is that it can be used to help dissolve additional solid lime into limewater. It does this by reducing the hydroxide concentration in the limewater:
10. CH3OOH ----> CH3COO- + H+
The H+ combines with OH- in the limewater:
11. H+ + OH- ----> H2O
The actual dissolution of Ca(OH)2 is limited by the multiplication product of the calcium and hydroxide concentrations in the limewater as shown below:
12. Ca(OH)2 ----> Ca++ + 2OH-
13. [Ca++] x [OH-] x [OH-] <= 5.5 x 10-6
where [Ca++] is the concentration of calcium (in moles/L) and [OH-] is the concentration of hydroxide (in moles/L). Consequently, if you reduce the concentration of OH- via equations (10) and (11), then more Ca(OH)2 can dissolve into solution and still meet the equation (13) requirement.
This would seem like a concern, however, since losing OH- might reduce the amount of alkalinity delivered by the limewater. Luckily, this is not the case. While the OH- is temporarily reduced by the acetic acid in the vinegar, when bacteria metabolize the acetate, they release it back to the water:
14. CH3COO- + 2O2 ----> 2CO2 + H2O + OH-
Consequently, additional solid lime can be dissolved into limewater using vinegar.
How much can be used? The more vinegar that is used, the lower the pH of both the limewater and the aquarium will be. One reasonable point to shoot for is to add about the same amount of total CO2 via the vinegar as is needed by the lime to form HCO3-. This balance is roughly matched by using three level teaspoons of solid lime per gallon of limewater, and 45 ml of vinegar per gallon of limewater. For those aquarists choosing to use vinegar in limewater, these values are a suitable starting point. Note that the pH of the limewater is still quite high, so slow dosing is usually required.
What kind of vinegar should be used? Luckily, cheap distilled white vinegar is likely the best. More expensive flavored and colored vinegars, such as red wine vinegar, will deliver other unnecessary organic molecules to the aquarium, and are best avoided.
Anemonebuff
New member
The kalk should have a pH of 12. That is the only way I know how to make sure it is mixed right. IMO it is pretty hard to mess up 2 teaspoons per gallon.
Alaskan Reefer
New member
It's very hard to mess up full strength kalk either via measured teaspoons, measured pH, or my preferred method, dump the whole can into the reservoir, add water, and stir. Come back and refill later after empty, stir again. Repeat as needed.
A dosing pump or dripper works well. 
