Seedlings look great but they're kinda skinny.

This is my first aeroponics grow and everything seems to be going ok but I have a question. Everything is spot on regarding Ph and nutrients but I'm into my third week and the seedlings look too skinny.

I've adjusted the height under CFL to about 4 inches and the leaves look great and healthy but the main stems can't seem to support their own weight.

I've already lost one when it fell over and broke so I've staked them with toothpicks and string. They're about 5-6 inches tall, several leaves, rock wool and healthy roots coming on strong.

Are they always this skinny to start?

yup that sounds about right. if anything try blowing on them lightly a couple times a day. this imitates as if a light wind was blowing on them and they will develop a thicker stem to support themselves.

also you shouldn't be feeding them nutrients this early. i usually wait at least 3 weeks after they sprout before i give them any nutrients or as soon as my plant looks as if its in need of nutrients. plain tap water usually does more than enough in the beginning.

Thanks for the reply widowAG. I've installed a small fan to keep a light breeze blowing over my seedlings and I'm hoping that helps to make them stronger. Like I said, other than the skinny stems they look beautiful.

In regards to your suggestions on nutrients, you're probably correct. This is my first hydro grow and I'm keeping the nutrients very low to start until I'm ready to transfer from my cloning/seedling chamber. Right now they're at around 300 ppm.

Once again, thanks for the reply.