7 Pot looking bad

[Delta]

The 7 is getting the same amount of water as the others but is not looking good. Should I snip off some of the wilting leaves? It has been under light (t8 wide spectrum) for a few days continuously but the other plants have as well and look fine. (I have had to leave the light on because I germinate using the heat from the ballast - 83 degrees.)
 
https://scontent-b-lga.xx.fbcdn.net/hphotos-prn1/t1.0-9/10150626_10151991114110723_5096173571099100678_n.jpg
 
https://scontent-b-lga.xx.fbcdn.net/hphotos-frc3/t1.0-9/10277794_10151991114390723_1440949040155982380_n.jpg

 

[geeme]

My first thought was fertilizer burn - you aren't giving them any yet, are you? If you are, stop, as they don't need it while they still have their cotyledons. If you're not giving them any, what type of medium are they growing in - starter mix or potting soil? Starter mixes have no fertilizer in them but most potting mixes do - that alone can be too much to cause damage to the babies. 

 

[Delta]

geeme, the medium is a mix of organic potting soil and seed starting mix, the same as all the others. "that alone can be too much to cause damage to the babies." I should note that the 7 pot is 5 weeks old. Here's a pic of what I'm using for mix. 
 
This came on all of a sudden btw. All other plants look good. They are slow to grow but they look strong. 
 
https://scontent-a-lga.xx.fbcdn.net/hphotos-prn2/t1.0-9/1497476_10151958370350723_207890918_n.jpg

 

[Delta]

geeme,
 
The 7 seems to be doing much better...less light, more water. Maybe I missed him last time watering. Only thing I can think of.