First off, by medicated do you mean with amprolium alone?
The white runny dropping is not normal. The temperature is normal. Birds don't really run fevers. Their normal temperature is around 105.7 degrees and can safely go above that. (Of course, we're not counting overheating due to environment as a fever - we're talking about their own body temperature going up without external factors.)
I wouldn't use colloidal silver anywhere except externally with birds.
Some questions for you. First, is this chick from a professional hatchery, feedstore that buys from a hatchery, or a breeder? Or were they home raised? If home raised, were your original birds from the above sources? Or did you get them from an individual who possible doesn't test for pullorum?
Is it possible that, due to the heat, she drank a lot of fluid and passed her urates (the solid white of droppings that are usually the bird's 'urine') along with the extra water? You'll want to check all of her droppings, keeping her separate and handling her as if she's a sick bird until otherwise cleared. Make a special note of all of her droppings within the next few hours.
Her weight - is she thin about her keel, as if she's being pushed around? Or is she quite heavy? What breed is she?
Put her in a separate brooder, and make sure that they're not too hot. This can cause all of what you've seen. Check her and make sure she doesn't have mites, etc. Give her a batch of feed including some yogurt or (better yet) acidophilis tablets from the grocery store/pharmacy. You can find them in the vitamin section. You crush one of the tablets, mix it with some mashed egg yolk - make a teaspoon out of the mixture, and give that to her. You can add a little water to make it easier to eat. If you have yogurt, use a 1/3rd teaspoon or so of yogurt (plain, or no chunks) with the egg yolk and try that. Leave her medicated crumbles in with her and some water. Do not put extra stuff in the water yet. If you feel she's too hot, you can use a small amount of pedialyte, or organic apple cider vinegar.
I would absolutely give her either the yogurt or acidophilus as whatever she has, until we determine what it is, is causing her digestive system to not work as normal producing excess water. Were she simply not eating much, the droppings would be thin, darkish (forest) green or bright green with bile.
Watch her eating especially - make sure she does. Watch the other birds. If any other bird shows the same symptoms, put them in with her. They do better with a buddy.
