Overwatering. What could I do to recover my plants?

Hi all.
I'm a new grower that started 10 days ago. I have put my plants from there JF's that I sprayed with water 5,6 pH to a new coco coir growing medium, 6 days now at first I gave them 2 days in a row 80ml of water with fertiliser like A and B grow at 0.5 EC and the leaves started to burn at some of the plants, the others are not so healthy green and since I put them to there new growing medium they didn't grow at all for 6 days. I try to keep temps between 24-27 and humidity around 50. What can I do to recover them.
Thank you.

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They're way too young for fertilizers. If you can flush them with Ph'd water it might help them

The first one doesn't look so bad but the second is crisp.

All you can do is to let them dry and then flood them with clear water, then let them dry. It's going to be a toss up whether the second one lives but the first doesn't look so bad.

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Don't need nutes yet, too small and young
Let em dry out and plain water for a day or 2

Thank you so much for the information guys!