"Nuts"? How do you flower your nuts?

Just kidding, I think you mean nutes though. Nutes as in Nutrients.

Yes, 15-30-15 is fine for flowering. Use at 1/4 strength at first, then every few feedings, bump it up to 1/2, 3/4, then full. Feed about once a week.

You want to start flushing your plant about 2 weeks before harvest to make sure you get all of the chemical nutes out. If you don't flush enough, the smoke will be harsh, especially using chems. Flush with clean water, and flushing means a heavy watering so water is draining heavily out of the bottom. Flush about 4-5 times heavily during the last 2 weeks. Good luck.