It depends on the size of the brooder. If in a relatively small space like a large moving box 75 watts is adequate. Ceramic heat emitters like those used for reptiles are much better. They allow you to regulate the day/night period, aren't as fragile as the glass types and are more efficient.
Red isn't necessary. It does tend to hide injuries but you can't provide a dark period.
After 3 days, I start the chicks on about 4 hours of darkness and graduate to 8 hours after a few days.