Looking great Roy!
I do have a tip in regards to DIY CO2, and making it last a bit longer than four days. This is the recipe I use for a 1 liter bottle.
- 150 ml. water
- 250 gr. sugar
- 2 gelatine "leaves" (the ones used for baking and such)
Add the water and the sugar to a pan, stir vigorously until it boils, then turn off the heat, and add the gelatine (which needs to be presoaked for a couple of minutes in cold water) and stir. Add this to the CO2-bottle that you are using (when cooled a bit, should you be using plastic), and let it sit and stiffen up in the fridge overnight.
The next day, or whenever you want to use it (it will keep for weeks and weeks, even in a regular cabinet, uncooled), you add 2 tablespoons of sugar and 1/2 to 1 full teaspoon of yeast (depending on the amount of CO2 you require; this will affect the longevity of the mix off course), mix it with some luke warm water, add it to the bottle, and then fill the bottle to about 4 centimeters below the top. CO2-production will start within a couple of hours, it will produce a lot at first, but that will taper down within a day or two. After that, it will EASILY last you a week or two, probably even three!