Do you have any pictures? I think you are running a combination drip and water culture system, but I'm not sure by the description. Also you didn't mention what watering cycle you were on (how many minutes on and off). Also pictures of your
drip system may help. I have just used tubing with holes in it for my dippers, emitters cost money and will eventually clog. If the tubing clogs I will just use a new piece of tubing, or simply re-poke the holes with a hot paper clip.
You can also just use the irrigation tubing from home improvement stores usually in the nursery with the sprinkler systems, or by the PVC tubing. That tubing comes in all sizes down to 1/8 inch, and you can get it with or without pre-drilled holes. Bottom line if the plants are wilting at all, either they are not getting enough water or the
nutrient solution is too warm. If they are not wilting at all, they are probably doing fine with moisture. Hydroton (
grow rocks) don't hold a lot of moisture, but the roots need air just as much as moisture.