How Long Can You Keep Brewed Iced Tea?

I've kept gallon jugs of brewed tea with nothing added for about 3 days many times. After about 4 or 5 days if not refrigerated, there is something that accumulates, and appears to be some type of fungus or mold. This has only happened when I failed to refrigerate the tea though.

I imagine it will keep for quite a while, considering it has no calories, if stored in the fridge, assuming you don't allow any bacteria causing chemicals come in contact with it (don't drink from the storage container, don't add sugar, etc).

I typically make iced tea in a considerable pyrex glass pitcher, but it does not have a protect, plus it takes up lots of room in the refrigerator. As it is wintertime, I typically have warm tea, but occasionally I like to get ice tea with luncheon. I Have got a whole lot of mason jars that I sometimes use to make smaller pieces of iced tea, to ensure way I can possess some choices, but I typically end them within 2-3 times.