If that is in veg, and LED.... Its highly likely you are giving too much DLI... daily light amounts with the light on 24hr is easy to overdo with LED.
1,000 ppfd intensity levels are fine in flower because the light is only on 12hr... but in veg with 18 to 24hr 1000ppfd is far too much... Along with high pressures from low humidity you will get nutrient issues, and etc