Need help fast!
 

Need help fast! I am doing a science project growing peppers with hydroponics. I have had great results until now. The plant is flowering and has formed one pepper. The problem is that the leaves are starting to wilt. I have changed the nutrient solution. What could the problem be?

You aren't shouting at your pepper plants are you? They hate that.
You may have a problem that is called damping off. Just change the focus of your science project from Growing with Hydroponics to Common Problems when Growing with Hydroponics.