Ken,
Baking soda is the primary ingredient in most aquarium buffer preparations. Most also contain Na(CO3)2, AKA sodium carbonate or washing soda.
You also may not be getting rid of enough CO2 from the tank. This could be caused by poor water motion (especially at the surface), poor ventilation of your hood, too small of a skimmer, etc. I have even heard of CO2 building up in modern houses because they are made to be so air tight.
Measure the pH of you water, then take another sample and aireate it for several minutes with an air pump and air stone. If the pH of the second sample is higher, you need to get rid of more CO2.
In addition to getting rid of more CO2, using kalkwasser to maintain your calcium and alkalinity will help raise the pH.
FWIW, even if you use Calcium Chloride in conjunction with Baking soda, you will still end up with an ionic imbalance, because as the calcium and alkalinity are consumed, you will be left with just NaCl and none of the other important ions (Mg, SO4, etc).
HTH,
Adam