OK, the title's stupid.
I really like the Mio Flavored Water Enhancer ("Enhancer"? Really?), but I'm not particularly fond of the price or the flavor selections (I can't stand Fruit Punch and the last Strawberry Watermelon tasked like it was contaminated by the mold release used on the package). In looking at the package though, it seemed as if it could be reused if I only had something to put into it. It turns out that some of the flavor packets sold in my local grocery store work perfectly.
So, why go through all this in the first place? Well, there are a couple of reasons ...
First, I really like the convenience of the Mio squirt containers, but as I said, I'm not in love with the selection of flavors. And I like many of the flavors of the other available drink mixes (can you tell where I live from the product picture?) but they're intended to be made up in 16 oz quantities (small serving size) to 64 oz quantities (large serving size). I usually only want 8 oz. Furthermore, I generally don't like my drinks cloyingly sweet; I want just enough flavor to add some taste to my drink (I use about half of what the serving sizes call for). So a squeeze container of other flavors would be perfect.
This begs the question of why not just get a different container? Honestly, I probably could, but all the containers that were easily (and locally) available didn't have the handy seal that the Mio containers do (if you've used one, you know what I mean). There are probably containers that have a similar seal, but at a certain point it takes way too much effort to find them. And besides, I'm reusing a container instead of throwing it away. That's gotta count for something.
The second big reason is cost. One of these containers costs about $3.50 in my local grocery store. The two drink containers in the picture cost about $1.50 and $2.00 respectively and each will refill the repurposed Mio container three times (translated: it's MUCH cheaper).
So, how do we do re-purpose the container?
Step 1: Set up
First, let's assemble our materials. We're going to need [at least] one of the Mio containers. The best way to get one is purchase it and proceed to enjoy the wonderful liquid water enhancement it provides. When it's empty, save it. Once you've got the container, you'll need to head to your local megamart and purchase a package of drink mix. My wife likes the Raspberry Lemonade, but I'm really partial to the Passion Fruit. Go with what you like. You'll also need a knife (to cut off the exterior label), a small container to mix the drink syrup in (mine's an old sterile specimen container that used to hold hops from when I homebrewed), and a whisk for stirring.
The drink containers in the picture (Raspberry Lemonade and Passion Fruit) has six packets each of which makes 8 cups. Each Mio container makes 24 cups. Theoretically, you could use 3 packets at a time and have exactly the same serving size. Personally, that doesn't work for me as there isn't enough water to dissolve the mix (and still stay under the capacity of the Mio container). Hopefully this will become clearer in a later step. Nonetheless, using two packets gives you a minimum of 16 servings, and in my case it's closer to 30 servings (like I said, I don't like it super sweet).