Cannabis plants take certain nutes to grow well! If you I was you I would have your friend get the basics! Get a bottle of Veg nutes, Bloom nutes and a bottle of cal-mag!! And follow the the instructions on each bottle! Fox Farm brand nutes are great for beginners because they are easy to use and very forgiving! Some brands are a little more touchy than others! But choose whatever brand you want! But remember if he’s growing auto flowers then less is more! Start out with half doses and work your way up to full dose depending on how the plants react! I hope this helps you and if you have any more questions feel free to get to me directly on my wall or tag me! Thanks 🙏 have a good day and good luck 🍀 to you and your friend 💯🤜🤛