Light Yellow mold, and curling(down) leaves

I have two seperate situations, one of which I am pretty sure I know the cure.

My oldest has a thick stem, and just reached about 18 inches. it is in a closet and was recently transplanted, about a week ago. it's approximatly 8 weeks old. I think I may have damaged the roots, but the soil is still very damp. I will check drainage, but I don't want to handle it much. should I add sand and perlite? I have bags of both. the leaves are curling downward, and the very lush looking grow tip has stopped in it's track's. the leaves are dry and like sandpaper. the edges are starting to get frayed and either yellow or brown/black.

The second situation is a 12 plot in another closet, which appears to be doing phenominal. they are in a tote, and I removed 2 to allow for more growing room. the bottom two (not the epicotle) leaves are wilting, but I beleive that is normal, I generally clip these. I noticed a yellow mold a few weeks back, and pulled the top layer of soil off, but I beleive it's growing down around the edges. what can I do? sand? less water? I was watering these every 2 days, but I have severly cut back to twice a week. is hydrogen peroxide safe for the plants?

thank you very much for all your help and concern

 

Bump? Could someone help? I have no idea what to do, I tried adding sand to draw the water out, my largest plant, with the curling leaves looks like it hasen't taken in any water in the last 5 days. the soil is soaked. it should be draining...

 

I have no camera, but is there a way to kill mold? will hydrogen peroxide work without harming the plants? I used a perlite sand mixture to the top of the soil to hopefully draw the moisture out.