Small stalks for week 7?

[Dbdigger]

This is our 3rd grow. Last grown only yielded 8 oz for 7 plants. We had a PH problem. This grow We are trying to be patient, but feel the stalk structure is small for being in week 3 veg, week 7 from germination. Thoughts?
lights are all the way to the top of the tent. 50% power. FF Happy frog, GH trio. My light & tent info are in my signature line.
there are 4 Blueberry Diesel, and 2 Durban Purple Punch.
thanks gang

 

[PRIMO]

Ya want a better yield? Might wanna think about getting em outta the solo cups.

 

[Dbdigger]

Ya want a better yield? Might wanna think about getting em outta the solo cups.

They are in 1gal pots currently. Then we move to 3gal fabric, or 5 gal