So, you have a Sodastream and have just run out of Sodamix. You could always buy more, but what if you want to make flavors not offered by Sodastream? What if you want to save even more money?
As you may have figured out by now, putting powdered drink mix into carbonated water doesn't work very well (unless you're going for a Diet-Coke-and-Mentos-style reaction). By saving your old Sodamix bottles, you can refill them with dissolved drink mixes and still use the measuring cap to make perfect soda every time.
Step 1: Gather materials
To make your own mixes, you will need:
Empty Sodamix bottle
Measuring cup with marks for milliliters
Non-carbonated drink mix that makes 10 or 12 quarts
You can start by cutting the old label off of the bottle.
Step 2: How much water?
Most drink mixes will make either 10 or 12 quarts, and for the purposes of turning this into a soda "syrup," a quart is close enough to a liter. The Sodamixes originally came with 500 ml of syrup to make 12 liters. If your mix makes 12 quarts, fill your empty Sodamix bottle with 500 ml of water. If your mix only makes 10 quarts, then fill the empty Sodamix bottle with 420 ml of water. Now add all of the mix packets to the water, put the cap on, and shake until it's all dissolved.
Step 3: Re-label and enjoy!
Now you can add your own label to the bottle, tape on the label from the drink mix canister, or leave them all blank and make mystery soda. Since your homemade Sodamix is the same strength as the original, you can still use the lines in the cap to measure. Enjoy!