seedlings need help

When plants were 9 days old I gave them nutes. They started showing burn signs and changed to filtered pH 5.8 water. They looked great then a week later the ends of the larger leaves looked like they had a brownish yellow dust on them but no dust just that color. Now top leaves have yellow stripes and bottom leaves are dying on the ends. Please help!

Post pics and all vitals, and never give them nutes until 3-4 weeks old...

9 days old does not need fertilizer. I am growing in a decent potting soil and just gave first feed (Weak) at day 21. To much water and nutrients will hurt small plants.

Computer dead using phone, don't think I can cut and paste. Growing in hydroton accelerated technologies Stanley and Brian combo. Temps are 72-80, adding co2, small fan in box.

double post this thread is