Noticed yellowing of some leaves. Last feeding was just PH water @ 6.7 with a little bit of cal mag. Before that plants were given700ppm@6.5

What is the pH and PPM of the runoff? You mention what you're putting in but what you're putting in often isn't what's coming out. I suspect pH lockout.

could be a nitrogen deficiency

what week or day of veg are you on?

have you started feeding yet?

what type of water are you using? Ro, Tap, Filtered...

what is your ph and ppm run off?

what type of lights are u using and how far away from canopy?

grow tent is a 2x4x5

growing in fox farms soil

nutrients used are VEG+BLOOM dry nutrients

plants are still in veg

temps around 67-72°

humidity around 50-60%

Your going to want to include more information in your post, to receive an accurate diagnosis. I suggest reading the 2nd thread from the top of the forum. It's called "Read me first". 👍