Need help identifying plant problems

[arcrad]

I have 3 plants started from bag seed about 7 weeks ago. They have been under 154 CFL watts totaling 8800 lumens which is now probably too little light. I switched from 18/6 to 24/0 about a week ago in order to try to speed up the seemingly slow growth. The soil is a mix of MG with time release ferts (i know, i know) and topsoil taken from the backyard garden. The pH of my clean water, water + H2O2 and water + nutes are all around 6 - 6.5. The temperatures within the box hover around 80 - 90, but that is taken from readings with a cooking thermometer that has been heated far past its range.

summary
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7 weeks in
3 plants from bagseed
154 CFL watts/8800 lumens
18/6 for first 6 weeks, 24/0 for last week
pH's ~6.5
80F - 90F
soil: MG mixed with garden soil



I believe plant 1 is suffering from nitrogen toxicity and over watering, causing the drooping and the dark color. Plant 2 has a healthier looking green color, but growth is still slow. Plant 3 is the youngest and seems to be the healthiest, except for an overall dark green color.

Plant 1 is my main concern. I fear that the yellowing is going to continue to work its way up the plant until there is nothing left.

I have read that nitrogen toxicity causes clawing, slow growth, weak stems and twisted leaves. Both Plants 1 and 2 have all of these conditions. Note the orange circle on Plant 2.

I have given the top section of the main stem of all 3 plants a light bending and they seemed soft, almost spongey. If I bent them over too much they would stay bent. The lower parts of the stems seem stronger. How hard should it be to bend the stems? How do I know if mine are "weak"?

So far it seems like nitrogen toxicity in all three plants.



What do you guys think?



Here is the watering log for the last couple days: