Looking good.
What's your res running like? Ppm or EC changing in any direction as they feed?
Looks like your ppm/EC could be falling on the return. Meaning they are feeding. Looking a little pale, not much, but a little.
In EC when I ran hydro if it went in either direction by more than 0.2EC then I would adjust it by adding water or by adding more nutes. If it fell I would up 0.2EC. if it up'd then i would add water to reduce nute strength.
J