A couple drops of Nutridrench straight on the tongue, then a couple drops plain water to wash it down...
Amoxicillin is a good start, check out Fish Mox in fish meds...
I can never get that horrible nutridrench dropper to get even close. I always have to put it on the tip of my finger and wipe it on the beak. I give it to all hatchlings before they go from incubator to brooder.