New growth looking to yellowish

Not toxicity; keep the drops (the most accurate by far). This is a """deficiency"""; your plant health is too strong for it to be anything but what I'm about to say. You need more calmag. In flower those top fan leaves and new leaves are really going overkill to reach for the sky! They are photosynthesizing on overdrive! Calcium and magnesium are two of the three most important macronutrients for this process. The other one is nitrogen, which is a mobile nutrient (Meaning it can be moved throughout the plant's life at will) Calcium and magnesium are immobile, meaning when the plant uptakes calcium and magnesium, it has to decide where to store it right away, and that's where its going to be. SO! Add some calmag! If you have an ec meter add .2-.4 ec a week during your feed (or whenever u water) until week 5 of flower (kinda when that heavy calmag load ends, but this is also cultivar specific) If the yellowing continues, you just making your plant live life as fast as possible. She is loving life, and when this "stretch" is completed you will see those fan leaves turn right back to normal. BTW: You are killing with this grow 😎

Hola! Yellowing of new growth during the flowering stage could indicate a nutrient deficiency. Since you're maintaining a pH range between 6.0-6.5 and your light is at an appropriate distance, consider checking the nutrient levels in your soil or growing medium. Review the nutrient requirements for the flowering stage and ensure your plants are receiving adequate amounts of essential elements like nitrogen, phosphorus, and potassium. If you're using specific nutrients for cannabis, check their recommended dosage. Additionally, be cautious with pH drops as they may not provide the precision needed for accurate measurements. Consider investing in a digital pH meter for more reliable readings. Addressing nutrient issues promptly should help improve the color and health of your plants. Keep a close eye on their response after making adjustments.

Your plants need some oxygen dó you have intake fan

Definitely a toxicity, nothing to worry about. Dial back nutes slightly. Watch for more lockout signs. Please consider selecting me as the answer so I can be entered for a chance to win grower of the month contest I would really appreciate it 😊

high levels of p or k can cause new growth to have chlorosis. if it fills in well, less to be worried about. if you amped up these things lately, maybe dial back a bit. tips burning is a sign of several different things, but also p or k tox.