N.,
There's a lot of research linking juice with childhood obesity and tooth decay. You may want to skip it for now- and later. The real fruit is more important for her to be eating because it contains more nutrients, less calories for its volume, and the fiber that helps your body to process the natural sugars more slowly. Juice lacks the fiber, is processed very quickly resulting in a spike in blood sugars, and is very high in calories for a small amount. Pedialyte is a replacer for lost electrolytes when your child is sick, throwing up/diarrhea, and is not recommended for an otherwise healthy child as it could disrupt the natural electrolyte balance. If you do choose to introduce juice, wait until she's older (1 year is best), buy only 100% juice (watch labels- "made with 100% juice could mean it has just a little bit of 100% juice and a lot of corn syrup! Ingredients should list juice/water only, and sometimes calcium or vit.c), and limit amounts to 4oz per day. Don't put in a sippy cup or bottle- the sippy/bottle with juice really contributes to tooth decay. As for water, you can introduce it in a cup (even a cup without a lid- your daughter is ready for you to help her learn to drink that way!) at each meal now. Just a few sips at a time as she'll be used to the taste of water before you know it! But at this age, you want to be careful not to fill her tummy with unneeded things- too much juice or water will fill her up where she should have your milk in there for nutrients. So just a little bit will do. Your baby doesn't really know what she's missing when it comes to variety and fun foods, so you get to decide what's fun! Stick to whole foods now, and you'll have less troubles with picky eating later. Add funky fruits like star fruit, avocado, and such for variety, and be creative in how you cook her veggies- lightly steamed, cut, chopped, ground, mixed, add colors and textures and seasonings. Good luck!
H.