Raising dKH (DIY)
 

I have been reading this
http://reefkeeping.com/issues/2006-02/rhf/index.php#5
Now my question is, Can i just do the Alk part and ignore the calcium part ? Since my calcium is fine only my dKH is a little bit low

Yes, you can certainly raise your alk alone to get the levels you want. After reaching desired levels, then use your calcium reactor to maintain both, or 2 part or kalk or whatever method you use regularly.

I have been dosing Alk alone for the past 2 weeks as my calcium levels were too high for my liking (460 plus) and my Alk was at around 7. I turned off my calcium reactor 2 weeks ago to let the levels naturally drop on its own and have been dosing Alk daily to maintain it at 7. My calcium levels are now at 440. As soon as my Calcium drops to 420, I will put my calcium reactor back online and cease dosing Alk daily.

Hope this makes sense.

Yes, you can use one of the 2 parts to raise your Ca or Alk. Spread out the dosing among a few days to prevent big swing.

Be careful about how you are using unbalanced amounts of the Ca and Alk parts. Ca and Alk have a complex interrelationship that cannot be ignored. Increasing Alk too quickly and too much can pull down your Ca. Also, you must make sure that your Mg levels are where they should be or your in for some frustration. The key is to take things slowly and do a lot of testing and notation of results.

Here's some more fun reading:

http://reefkeeping.com/issues/2006-06/rhf/index.php

See also the additional links at the bottom of that article, specifically from this:
"If an aquarist is supplying a balanced additive to his aquarium, and calcium seems stable but alkalinity is declining, it may very well be that what is needed is more of the balanced additive, not just alkalinity."

which is taken from this article: http://reefkeeping.com/issues/2004-12/rhf/index.php

Yup...yup...live by these words.