Soda Ash (baked baking soda) question

EMUreef · 07-17-2011, 01:59 AM

This question is for anyone that has gone through the process of making their own 2 part.
My question comes into where you make your own stuff to dose alk.

i got the process down. bake the baking soda for an hour at 300 degrees take the left over stuff and mix it in with a gallon of RO water than your set to use.
suppose to mix 2 1/4 cups.

My question is, if you mix more of the soda ash will the product be higher in dKH? or whatever its called.

or does there just reason a point that no matter how much you add you dont get any higher values out of it.

anyone follow that? lol

Flynnstone · 07-17-2011, 09:18 AM

not stealing the thread but, on that same token...

when turning Baking Soda into Soda Ash you are burning off the Hydrogen. when you mix the Soda Ash into the water and allow it to sit for hours or days before use. what would be the difference from just using the Baking Soda?
does the Ash allow for a more concentrated solution, as asked above?

BeakerBob · 07-17-2011, 10:19 AM

The principle purpose of heating the baking soda to convert to soda ash is to drive off the C02 and H2O. The formula is shown here: 2 NaHCO3 -> Na2CO3 + H2O + CO2

Recipe #1 developed by Randy Holmes-Farley is recommended for use on tanks that have a normal to low pH.

Why use heated baking soda for tanks with low to normal pH? Because you have driven off the CO2, adding this alkalinity supplement will cause the pH of the tank to increase slightly.

If you use baking soda out of the box, the addition of the alkalinity supplement will cause a slight decrease in the tank pH due to the presence of CO2. Hence, the reason to use Recipe #2 for tanks with a higher pH.

The answer to the question is YES, dissolving more heated baking soda (now converted to soda ash) will increase the alkalinity potential of the supplement. However, there is a point where the solution will be saturated and the soda ash will no longer dissolve. This is the same reason that only 1 1/8 cups of baking soda is used in Recipe #2....more will not dissolve.

For the second post about soda ash in water sitting around and converting back to baking soda (with the CO2 issue): As long as it is kept dissolved in a sealed 1 gallon container, it is good for a long time and will not decrease the tanks pH when added as a supplement.