Leaf problem

[str8haze]

I noticed the problem several days ago. This is a 56-day ebb and flow in smart pots from seed still in the vegetative stage. 73 F and humidity is 60%, Rain water,
ppm 902 temp 18.6 c, runoff is 708 and temp16.6 cPH 5.5 runoff is at 7, 70 % coco coir and 30% perlite, 4x4 tent, Quantum Board HLG 600H at 75% about 18 inches from grow, 18/6 light schedule (thinking of switching to 24/0 light schedule for the final week before bringing to flower, feeding General Hydroponics at half strength, CAL-MAG -- I have also just started using for about a week some earthworm casting 01-0-01 and Humboldt's secret 0-0-2. Any help or recommendations? I was thinking of flowering 12/12 in about a week on day 63. thanks

[buzz]

Looks like they could benefit from a flush and some calmag

[str8haze]

Should I flush them all or just her

[buzz]

Sorry good luck Peace

[buzz]

It’s hard to tell in all the pictures but what I would say is it wouldn’t hurt so that they go in to flower as strong as you can get the little Angels

[str8haze]

thank you

[buzz]

Your welcome good luck ✌🏻

[Mr.furley]

You also need to more that ph up. 5.5 is low, calcium magnesium need the range of 6.0 and up.