Spear leaves are yellowing.

I have 4 plants that popped out of the rockwool last Thursday (3/26) and are showing signs of yellowing. Yesterday I gave them 2ml of Micro/bloom to try and help them out a bit. It only raised the ppms 250.
I have been giving them straight water before that, and every time I water I PH to 5.7-9.

The only thing I can think of is my ph meter might be off. Since I used some calibration fluid and poured it back in the bottle, which I have learned has ruined the bottle. Or maybe the rockwool is to saturated with water?

What type of water are you using? Maybe u need CalMag? I'm just guessing

you are already fucking up by using chemical fertilizers on your first grow. Use organic earth juice original fertilizer. You do not even need a pH meter or any meters at all. Just need tap water. It's so simple. Trying to use chemical fertilizers on your first grows going to be a complete nightmare in somebody's going to have to hold your hand every day to make sure you don't screw it up.

Sunny I am using tap water.

MrBelvedere, this is not my first grow only my first grow in rockwool. I have grown a few times in coco.