DIY CO2 issue
I am having some issues with my DIY mix at the moment and would like some advice. I am using 2 nutrafin bottles with a DIY mix on a 20G high tank. In the bottles I put around 1/2 cup sugar, 1/4 tsp baking soda, and a bit less than 1/4 tsp champagne yeast. My issue is that I made the two bottles on Monday with hopes of being able to swap one out each week to keep a steady supply; however on Friday the mix has burned itself out.
How can I make the mix last longer using the two Nutrafin bottles. Would simply increasing my baking soda do the trick?
Also if it matters the tank is at 78*F, the house is set at 72*F.