Adding calcium via water changes...

[overCee]

Hi,

I am relatively new to reefkeeping and desire to stock my tank with LPS-style corals. I currently only have a fungia plate coral added in the last few days. I just measured my calcium level and it is 275 ppm, which is too low. My alk level is also 2.5 meq/L which is also on the low side.

Since I would prefer to avoid the expense of topoff pumps and reactors I was hoping to determine a method to add calcium (from limewater) via my weekly 10% water change.

From the article What Your Grandmother Never
Told You About Lime (http://reefkeeping.com/issues/2005-01/rhf/index.php#3) I have read, "Adding, for example, 1/4 teaspoon to 40 gallons 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."

This is a perfect bit of information for me since I have a 30 gallon Oceanic cube with a 10 gallon sump.

I was hoping that I could add a quarter teaspoon of pickling lime to the 4 gallon waterchange water that I add to the tank every week.

Does this seem reasonable? If not, what else do you recommend I try?

Can I increase the amount of lime added by using vinegar? If so, how much vinegar should I use (and what kind? I assume white vinegar).

Thank you.

[Randy Holmes-Farley]

As it stands now,you need to raise the calcium level with a calcium only supplement, not limewater. Any balanced calcium and alkalinity additive will push alkalinity through the roof if you try to boost calcium by that much. Calcium chloride is the best way to go. Dissolve it in some fresh water and add over a couple of days with a measurement in between to see how it is going.

This calculator shows how much to use:

Reef Chemicals Calculator
http://home.comcast.net/~jdieck1/chem_calc3.html


and this article guides you through that process:


Solving Calcium and Alkalinity Problems
http://www.advancedaquarist.com/issues/nov2002/chem.htm


Then going forward, the limewater is an OK additive, but you cannot add it to water change water. You'll precipitate calcium carbonate and magneisum hydroxide if you do that.


It really is optimal to drip it in, but if the demand is very low, you might get by with a once a day addition of diluted limewater to replace evaporated water.

[XeniaMania]

I've been mixing 2 teaspoons of Kent Kalkwasser mix in a quart of water and dripping about 3/4 of that quart into my tank every other day. Needless the say my pH and Alk are at the max level, running tests on both the colors are at the max. Testing my Ca tonight w/ Saliferts Sr test, it shows it's at 380! Mg is at 1350, so I guess my corals are sucking up Ca that quickly. I guess going w/ Ca only additive is the only way to go at this point? TIA.

Also, I've started dosing Red Sea's Calcium +3 which is:

Calcium and strontium are utilized by corals, other calcareous invertebrates and seaweed. Iodine and molybdenum are essential for the cell processes of the aquarium inhabitants. These elements are used up faster than can be compensated by partial water changes.

Calcium +3 is the only formulated calcium replenisher which combines strontium, molybdenum and iodine in a unique manner so that no cation or anion displacement occurs when added to the aquarium. This formula will promote the growth of hard and soft corals and other invertebrates.

[Randy Holmes-Farley]

You might need a one time boost for calcium, but you will not need routine dosing of calcium (assuming you do not add buffers) since the limewater (kalkwasser) provides calcium and alkalinity in the appropriate ratio to balance calcification, and if you are not adding enough, alkalinity drops first.