baking soda

[maguz921]

I wanted to bring my Alk up slowlly from 2.86 to 3.40/3.50 I have been slow dosing w some baking soda. I think it actually went downto 7.4 any cue. Should I do a water change? Any clue?
Cal 375
ph8.2/8.3 (D) 8.0(E)

[Randy Holmes-Farley]

You probably just need to dose more. This calulator will suggest how much is necessary:

http://home.comcast.net/~jdieck1/chem_calc3.html

This article may also help:

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