Tip of the leaf became yellow

A.Likely this is the PH adjustments that had to be made. This only takes a few hours to show up. It could be the beginning of nutrient burn.. 1.5ml/L is very strong for Mineral Magic... typically we use 0.2g/L or 0.4g/L. The measurement on the jar of Mineral Magic instructions says 4g for every 10 liters.. 1.5g/L would be close to 15g for every 10 liters.. 3x too hot for the setup if the numbers are all listed correct. B. if you are using EC 0 water, you will need cal-mag, literally right now. The water I use for my DWC is 200ppm from the stream with high levels of all naturally occurring minerals like Iron, Calcium, Manganese, Magnesium, Phosphorus and Silicate. I still use Cal-Mag sometimes depending on the breeder. FastBuds seems to be cal mag thirsty. I run all of my DWC grows 28-30 degrees during the day, 20 degrees at night. The temperature split of 8-10 degrees makes them grow very fast from what I have experienced. I am a strong believer in the 10 degree difference in night versus day temperatures like in nature. For mars hydro I use 2x TS1000s, intensity 100% about 100-110cm away (permanently mounted in top of mars hydro tent) it allows for the temperature at the plant to be around 28 all the time. I never touch the light's intensity knob until the last few weeks of growth to simulate the summer to autumn season which works very well! Plant is looking good, we have all had this happen, no worries! She will be strong! She has good master growing her!