not sure what this is

Hey, buddy! 👋😇 The plant is showing you a phosphorus deficiency - red stems, red spots on the stem, and the appearance of yellow and soon brown spots on the leaves! - All of this is phosphorus deficiency! From your diary, it's not clear what nutrients you're using, but one thing is clear - you have the wrong soil pH! First of all, set the necessary pH for flowering. In soil - 6.3 pH 😇👌 Water with less nitrogen and more phosphorus. If you're using any popular or common nutrients, then make the ratio Grow:Bloom 1:3, i.e., for every 1 ml/l of Grow, add 3 ml/l of Bloom! Instead of Grow, you can use Micro! 😇👌 Good luck, bro! 😇👍