Your plants do look like they have been stressed and are growing slow. This is why it is best to start with bagseed. Eventually you will find your rhythm, and learn alot along the way.
I do have a couple suggestions for your hydro setup though. First off those tubs are not light proof, if you were to hold the tub up to a light and look from the inside you will see this. Wrap the tub with some black duct tape or something else that will block all light out of the root zone/reservoir. This will help prevent algae growth and root rot. Second is get a water thermometer, and make sure the reservoir temp stays below 80F. (68F is ideal temp) Third is you want to get that rockwool down lower and completely covered up. Wet rockwool and direct light is a good recipe for algae growth. One last suggestion would be to start using Hygrozime in the reservoir, because you may already have some root rot. The Hygrozime worked awesome for me in getting rid of the dying roots and promoting healthy new growth. Also try to keep your hydro ph between 5.5-5.8.
Hope some of this helps you out.
Happy growing :smokin: