Reef Chemistry Question of the Day #94 Calcium and Alkalinity

[Randy Holmes-Farley]

Reef Chemistry Question of the Day #94

Which of the following actions will most likely permit adjustment of an aquarium with a calcium concentration of 320 ppm and an alkalinity of 2.5 meq/L (7 dKH) to match natural seawater with a calcium concentration of 420 ppm and an alkalinity of 2.5 meq/L (7 dKH)?


A. Adjusting a calcium carbonate/carbon dioxide reactor to add more CO2, increasing its output.
B. Adding limewater for a week, replacing all evaporated water.
C. Adding a solution of baking soda over three days.
D. Adding a solution of calcium chloride all at once.
E. Adding a solution of baked baking soda (baked at 300°F for one hour before dissolving).

Good luck!





























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[beaslbob]

b.
both calcium and alk are low.

 

[zemuss]

D if we are only raising Calcium

 

[DFW]

D..

 

[Nano sapiens]

D. It is the only choice that will raise Ca without raising alkalinity.

 

[tonizzy22]

Answer is A it will increase calcium and keep alk level and lower pH

 

[beaslbob]

Oh dern
I just noticed the alk was not low. Looks like D, adding calcium chloride will do it.
But then alk would lower also.
so perhaps Kalk is the correct answer after all.
I may be stubborn so I'll stay with kalk.

 

[mc-cro]

D. It is the only choice that will raise Ca without raising alkalinity.

of the options provided, I agree D is the only one that wont raise alkalinity, but I dont know that I would dump it all at once, that could cause it to precip. maybe its a trick question....

In E, what effect will baking have on it?

 

[Wiz]

Yup d

 

[jedimasterben]

She wants the D :shocked:

 

[zemuss]

mc-cro the option for E:Adding a solution of baked baking soda (baked at 300°F for one hour before dissolving) would be alkalinity based on this article:http://www.reefkeeping.com/issues/2006-02/rhf/ by Randy

 

[leptang]

Im going to guess D, but B would work too depending on the demand of calcium and alkalinity.

 

[hart24601]

F. Make a new thread "Help me adjust calcium Randy!!!"

 

[dallasg]

D...

 

[Randy Holmes-Farley]

And the answer is...D. Adding a solution of calcium chloride all at once.
Congratulations to those who got it right!


Calcium chloride will boost only calcium, which is what the question called for.

Explaining the wrong choices...


A. Adjusting a calcium carbonate/carbon dioxide reactor to add more CO2, increasing its output.

That could boost calcium by the needed 100 ppm, but to do so, alkalinity will rise by 5 meq/L (14 dKH), missing the alkalinity goal of 7 dKH.


B. Adding limewater for a week, replacing all evaporated water.

If you added enough in excess of the demand, this might work to boost calcium, but, like A, will boost alkalinity by 5 meq/L (14 dKH).


C. Adding a solution of baking soda over three days.

This will only boost alkalinity and not calcium, which cannot meet the goal.


E. Adding a solution of baked baking soda (baked at 300°F for one hour before dissolving).

Like C, this will only boost alkalinity and not calcium.

Happy Reefing.

 

[beaslbob]

Looks like I'm back in the groove again.
Of using the wrong ans.:wink: