Листья сохнут по краям

potassium availability is highest above soil pH of 6.0. At low pH, potassium availability is generally low. Low pH decreases the soil's ability to keep supplying potassium to plants, therefore potentially increasing the need for additional fertilizer applications or liming to raise the soil pH.

Chloride is screwing up pottasium distribution.

Difficult one........ Potassium was my clear thought off the bat but seems very odd as chances of showing deficient during veg is minimal. I think your problem might be chloride. Chloride is responsible for transport of nutrients such as potassium (K+), calcium (Ca2+) and magnesium (Mg2+) since it acts as a counterion to maintain electrical balance. Chloride is commonly found in nature—from seas, to soils, to the air—it’s everywhere. It is a monovalent anion, having a single negative charge (Cl-). Plants take up the element chlorine in this anionic form. Under standard conditions chlorine (Cl) is an unstable, yellow-green gas. Unlike Cl- , free Cl rarely occurs in nature.

Could be a few things— one or a combo: Heat stress Nute burn Too much/ too little watering schedule—- be consistent with the water