My opinion without having much to go on besides pictures --- severe nutrient burn and light bleaching. Help us, help you. What medium are you using? Nutrients? Feeding frequency? Lights? Temp? Also need to know pH in and out, ppm/EC in and out, temperature, and RH might be helpful. Give us more to go on and we can likely help. I think this grow is probably beyond saving by the looks of things, but with the right information I'm sure you can be successful in the future.