1800 - 2000 ppm is about where I have them during the final two weeks. The plants are too late in maturing so over nuting shouldn't be a prob. Just be sure to flush very good or you will taste the nutes. Just my 2 cents. Maybe you should try both. One grow with the ppm's like whoa and the next one laid back or how your friend recommended to cut back. See the results for yourself. The pics are of the last plant I flowered. Good luck.