I have not used distilled water.
The recipe I use is as follows:
1 gallon water
4-6 tea bags (I like to use 4 bags of green, and 2 bags of black.)
1 cup of sugar.
Boil water, add sugar until dissolved. Remove water from heat, add tea bags, steep as usual (I go about 6 minutes).
Chill the tea until around 70-80 degrees.
Add SCOBY and top off with 1 cup or more of your previous batch or "starter tea."
If you're growing from scratch, do a partial batch and add a bottle of original, raw GT Kombucha. Let it go until you have a healthy scoby, then do the recipe above.