Welcome Derek
I hope this works well for you.
Sweetened water is not something we should have on Atkins. We are trying to get away from sweets. Only plain water counts as water. So man up and drink it.
If you have splenda (and you are limited to only three a DAY - in total) count it as one carb each. But drinking sweet water is not helping your bloodsugar.
And don't forget to eat your veggies (do I sound like your mother yet
)