Keeping the pH of the water at ~6.5 and at 20/4 with our lights. Temp holds between 71-74. Humidity is reading 51% right now. Also getting a little tacoing on two of the plants so we tried moving the light away about an inch. Lights are about 2.5''-3'' away.
Looks like a tiny bit of nute burn.Also looks a wee bit over watered.If you have fed already its a bit early.They can go a few weeks,or more after poping without nutes. Unless it gets worse stop watering.If it gets worse.Flush then dont water for a long time. Pick up your pots right now.Then pick them up daily till the weight difference is much less.Then water.Thats how you tell.Although in veg with seedlings you will not want to get it fully dry,but still the pot should be a lot lighter. Feed when your plants tell you.In veg youll notice lighter colored growth at branch tips when it needs nitrogen.Bottom growth turning yellow however is normal dont feed because of this.Same applies for flower.Watch your plants learn what they are saying,Then feed appropriatly. Also I think PH 6.5 is ok,but I think you want it a bit lower.In veg especially around 6.2 ish for soiless medium like promix.
Thank you so let them dry out first and then give them a flush if they get worse? The top soil is pretty dry but when I stick my index finger in its all pretty moist and soil comes away wet on my finger.
Then they're definitely not due a watering yet. I think the finger rule is about two inches. Stick the finger in two inches - I go to the first joint below my knuckles of my pinkie finger and pull it out - if you feel any moisture then repeat a day or two later. When you stick it in and pull it out and there's no wet, not even a hint of cooling moist (caused by moisture on finger evaporating in the air), that's a good sign for watering. Obviously, going with the weight of the pots is a good measure, too.