Maintain Alk w/o increasing Calcium?

[mothra]

Now that I somewhat have a grasp on what alkalinity is (thanks Randy) I'd like to know what additives can be used to raise alk that will not also increase calcium levels? Also what long term solutions are there for maintaining alkalinity, I'm thinking along the lines of:

a calcium reactor is to calcium like a __________ is to alkalinity. Maybe there isn't any type of 'device' used to maintain it but since getting into this hobby I don't think I have yet found anything that someone hasn't built some sort of gadget for :)

This is a new tank (75 + 30 sump/fuge) and will primarily be soft corals. I'm hoping the calcium from weekly 2% water changes will be enough to keep up. Parameters right now:

ph 8.0-8.1
sg 1.025
amm, trites 0
trates < 20 ppm
calcium 480 ppm (using Oceanic salt)
alk 2.29 meq/L

All tests are sailfert, ph is digital meter, sg on refrac. Thanks again for your help.

[Randy Holmes-Farley]

You can raise carbonate alkalinity with three fundamental chemicals : hydroxide (which is how limewater works, although it also has calcium), carbonate, and bicarbonate.

So baking soda is a fine way to raise alkalinity. :)

I mention it in this article:

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

[mothra]

Randy - Thanks for the quick reply. You're a chemistry animal! I'll take a look at the artcile. I'm not much of a chemist myself (I know, it's hard to believe). I think I remember something throwing a brick of sodium into the pool being good fun for the family. :D

[Randy Holmes-Farley]

I think I remember something throwing a brick of sodium into the pool being good fun for the family.

I did that to a nonscientist roommate my freshman year at college. He was in the shower and it was little bits of sodium rather than a brick, but he was still rather surprised. :D

[mothra]

lol. I guess it really is a rite of passage for chemisty students.

[APynckel]

Originally posted by mothra
Randy - Thanks for the quick reply. You're a chemistry animal! I'll take a look at the artcile. I'm not much of a chemist myself (I know, it's hard to believe). I think I remember something throwing a brick of sodium into the pool being good fun for the family. :D

Naw. Now a brick of cesium would be fun :eek:

[mothra]

Randy (or others) - I'm planning to add some baking soda to increase my alk this weekend. Right now alk is about 2.29 meq/L and I'd like to be closer to 4 meq/L. The entire volume of our system is ~100g. So from what I've read 6 teaspoons will increase alk by ~1.2 meq/L.

How slow should I add this? I was thinking that I could add 3 teaspoons to about a gallon of RO/DI water and drip it in, then maybe next week do the same. Would I be better off to go slower than that?

Thanks again for you input.

[Randy Holmes-Farley]

Dissolve it in fresh water, and add it all at once to a high flow area. :)

[pszemol]

Originally posted by mothra
Parameters right now:

ph 8.0-8.1
sg 1.025
amm, trites 0
trates < 20 ppm
calcium 480 ppm (using Oceanic salt)
alk 2.29 meq/L

All tests are sailfert, ph is digital meter, sg on refrac. [/B] Is Salifert alkalinity test really so accurate to be able to determine alkalinity to a single hundredth of meq/l or this is kind of typo?
According to the manufacturer (http://www.salifert.com/pt/kh.htm) this test has resolution capability at 0.1 meq/l - how did you get the 2.29meq/l reading?

[Habib]

Originally posted by pszemol
Is Salifert alkalinity test really so accurate to be able to determine alkalinity to a single hundredth of meq/l or this is kind of typo?
According to the manufacturer (http://www.salifert.com/pt/kh.htm) this test has resolution capability at 0.1 meq/l - how did you get the 2.29meq/l reading?

If it was truncated to one decimal then it would make sometimes a jump in the value which would surprise some people and make them wonder. :)

[pszemol]

Originally posted by Habib
If it was truncated to one decimal then it would make sometimes a jump in the value which would surprise some people and make them wonder. :) I do not get it, please explain...:confused:

[Habib]

Originally posted by pszemol
I do not get it, please explain...:confused:

Als a basis the full 1 ml measures 16 dKH and the chart gives values in 0.02 ml increments.

The dKH values have been used to calculate meq/L

As an example the chart gives for two positions: 5.26 and 5.14.

Rounding the result to one decimal would give 5.3 and 5.1 so the difference is suddenly 0.2 meq/L while in many cases in the table truncation would give a 0.1 meq/L difference between values.

The instructions with table can be found at: www.salifert.com/instructions temp/KH-Alk Profi-Test.pdf

[pszemol]

Originally posted by Habib
Als a basis the full 1 ml measures 16 dKH and the chart gives values in 0.02 ml increments.

The dKH values have been used to calculate meq/L

As an example the chart gives for two positions: 5.26 and 5.14.

Rounding the result to one decimal would give 5.3 and 5.1 so the difference is suddenly 0.2 meq/L while in many cases in the table truncation would give a 0.1 meq/L difference between values.

The instructions with table can be found at: www.salifert.com/instructions temp/KH-Alk Profi-Test.pdf Thanks.