hello, i have just started growing again it has been 15 years and seems i have forgot everything i learned. i have some questions. i started with 15 fem seeds 14 sprouted i trans them into ebb and flow system. they are almost three weeks old seem real small, and now have started yellowing on the tips. think i have nute burn did flush. and also used 3 inch rockwool into hydrotron seems rockwool is retain to much water and hydrotron is drying what should my water schedule be. did read mj bible three times and jorge is a god but doesnt really answer specific questions. will get pics up soon. please help cant afford new seeds and put tons of time and effort.please help
Welcome to the forum. Nute burn will look like a burn, your describing a deficiency. Doesn't matter, flushing with one quarter strength nutrient at 2 times the pots capacity may solve the problem if you flushed by top watering.
3" rockwool into hydroton normally requires top watering for a few days until the roots get down into the hydroton. Your ebb and flow should be set so that it does not quite reach the rockwool once you have the roots set.
If you flushed from the top that should have taken care of that problem. I used to water four times for plants in 18-6 light beginning an hour after lights on and stopping 2 hours before lights out.
The hydroton may appear dry, remember it has lots of little holes and once you get the roots down into it they will probably be fine.
If you want to you could check one of the plants to see if the roots are 'down into the pot', of course that may kill that plant, may save the other 13 too.
We have lost a few plants when we forgot the top watering for the first few days, sometimes they do not recover. Hope I am wrong.
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