Are my hydro plants dying?

Their roots are very healthy, but the leaves look like they have dark spots on them.

We've grown them from seeds.

At first I thought I was just nutrients splashing on them, but it seems to be speakings, so I'm not so sure.

That rockwool cube is soaked, more than likely crown/stem rot inside the cube. I would cut it open and have a peek, it probably won’t last long in its current state

Is my rock wool not supposed to be soaking wet?

This is an airponics grow.

Rockwool should never be saturated, it’s hard for beginners to get the moister level just right in it. You should have hand watered it very little amounts (damp not soaked) under a light until root structure was larger and healthier, then put it in the aero pot with hydroton. I never ran aero before but you should have no rockwool and a neoprene collar around stock or hydroton in the net cup.

Changes made. Thanks!

Yup no problem, not sure if it’s going to make it need to make sure there is no rot, if no rot then maybe it will live. Looks like those next set of leaves down there are torched. Did you add any food/nutrients?

hydroton Hand water lightly

All of our roots are in perfectly white condition and looked great. I didn't see anything rotting.

Hydroton is a special rock, right?

Do we need to use it? We just have them suspended from the collars right now.

We have added some nutrients, pH is at 6, waiting on my ec meter.

Thanks again!

Ok first off stop giving it nutrients you are burning it with way to much fertilizer, it will need little to no food until it is farther along. Second, no you shouldnt use the neoprene collar with rockwool because will stay way to saturated. Hydroton will block water from direct contact with the cube, yes it will still get moist but won’t get soaked. Take that poor thing of the nutrients, ph’d plain water only for now.

The nutrients I added are at the level the label says is recommended for seedlings, and I added them because their growth had stopped, I'm watching them on a motion capture camera.

I agree with drgreentm. Add hydroton around the rock wool. You will get rot staying that wet.

Ya the bottle is a good baseline to start if new to the nutrient line but Not something you want to follow to a T, especially for seedlings. At its size now it more than likely only has a tap tap root looking to dig deep and then producing Thinner horizontal root structures.

This is what my seedlings look like when I start feeding.

You will start to notice foliage becoming a lighter more Pale green. This is a few days later at LOW feeding.

Over 10 years of growing and just barely starting to read about plant biology and this has helped me immensely by understanding how plants work. They like total balance if something is higher than what they need, like fertilizer, They will actually expel water from the roots to try to balance what’s available overfeeding does much more harm than good As you are also Robin things from your plant like Valuable H2O which causes it to pull water From its leaves which causes them to dry and burn leaving behind those nasty brown patches.

You need a way to test EC, and PH Of the nutrient solution, or else you will have no way of knowing what the Salinity of your water is especially if you are using tap water that may be hard and causing overfeeding.