Nutrient concentration build up in Rockwool Cubes for seedlings.

Good day all.
I cannot seem to find an answer to this question however "common sense" would suggest the answer is yes?
If one wets a Rockwool Cube with nutrient water and the water evaporates, wouldn't repeated wetting concentrate the nutes to the point where it kills the seedlings. Unless one shouldn't be giving seedlings any nutes at all until their roots escape the Rockwool Cube? Once the roots escape they will go into a high pressure aeroponic system.
Image 1 seedlings are doing great.
Image 2 seedlings are starting to show problems 3 days later.
I did move them under the Flexstar 645W Pro LED. Its possible the light was too powerful even at 48inches high and on 40%.
I've moved them out from the light now to see if they recover.
I cant figure out if its a light or a nute problem.
6 x Auto Ultimate.
1 x Gorilla Glue.

I start seedlings out in coco with straight tap water not even ph’d till they get a little bigger then I feed a very low ppm solution like 200-300 ppm until the roots get established. Not sure about the rock wool but it makes sense if your letting it evaporate then yes it will continue to build up in the rock wool.

I think the real question is why are you starting seeds in rockwool, feeding and using a 645w light on seedlings?
You're making everything super complicated for yourself. If you can't keep a seedling alive what makes you believe running hydro is gona turn out well for you

Starting in rockwool is great and easy. You only must know what you are doing. You stated you added nutes? What did you add and at what ratios? The nutes won't build up high enough to cause issues unless you are using too much.

I start in a dome and RW.Once you get some roots out the bottom I put them in a small dwc system and net pot.Food only splashes up against the clay pebbles,300ppm. Once roots come out the net pot then into final system.

Use a weak solution or allow 20% run off, I'd go with run off, you're correct in thinking water evaporates concentrating salts and it's made worse with low humidity and hot temps.

If it were me I wouldn't put them in the system until they were rooted sufficiently.

Auto seedlings in rockwool and a new grower. Wait for the follow up posts.

I germinated the seeds in paper towel.
Soaked the rockwool cubes in PH 6 distilled water with Terra Aquatica TriPart (0.5ml of each per liter as per instructions for hydro first roots)
Gently inserted the seedlings into the rockwool.
Placed them under my Flexstar 645w Pro at 40% power and 50 inches high - also as per seedling instructions.

I decided to remove the seedlings from the RW cubes in case I screwed them up somehow and plant in freshly prepared Palm Peat soaked in PH6 distilled water - no nutes. I've had great results with seedlings in palm peat in the past.

Really have no idea why these seedlings just stay the same size.

Attached new image.

Father Earth said:

Starting in rockwool is great and easy. You only must know what you are doing. You stated you added nutes? What did you add and at what ratios? The nutes won't build up high enough to cause issues unless you are using too much.

Click to expand...

Replied below thanks.

Little-Leopard said:

Replied below thanks.

Click to expand...

Somethings off with your nutrition. Have you added nutes?

Father Earth said:

Somethings off with your nutrition. Have you added nutes?

Click to expand...

Yes, I used Terra Aquatica TriPart (0.5ml of each per liter as per instructions for hydro first roots)