Agree with Antics.
Temp > humidity.
If you have a closed environment, you can easily adjust low humidity by foliar spraying, but 50% RH does t seem too bad.
I'm not a hydro grower, so I might be wrong.
As the week goes along, won't the plant be using the nutes, making the ppm lower?
I don't think you should be adjusting the ppm every day? Just when you change the water so you have the right amount of nutes until you change the water again.
Think...
Re: my bagseed chronicles....
I think your answers are already in this thread.
The soil looks too wet. (wait until the top is completely dry and then stick your finger in, if you feel "moist" then you don't need to water).
A dry period is good for the roots to search for more water and will...