Mutant growth

These plants have been on the edge for the last 2 weeks but I thought they were stabilizing, turns out I was wrong. I transplanted them 3 days ago and put them under a 600w hps about 28 inches above the plants. Temps are 80° lights on and mid to low 70s lights off with 50% RH checked at plant level. The older leaves continue to look bad and getting pale and a little crispy however the new growth is a darker green but a lot of the leaves only grow half a leaf off the main lateral vein or are missing parts off the main vein. They are in coco/perlite and I have been keping my ph between 5.8 and 6.2 with runoff being very close or a point lower. I have been feeding them GH flora trio but only at 1/2 recommended seedling feed strength when I do feed them because I thought at first I was over feeding. They are 3 weeks since sprout and seem very short and dense (all newer leaves growing on top of each other).Any suggestions what might be happening?

I'm thinking it's gotta be one of the following:

Poor seed genetics - Probably not...
Too much light - Probably not...
Too little light - Probably not...
Not enough nutrients - Probably not...
Too much nutrients - Thinking that's the one.

The reason I'm thinking this is because a seedling will live and grow healthy for a couple weeks on the nutrients it gets from water alone.
If it's been overfed it will take a while to straighten itself out - and in the mean time they will eventually be needing nutrients so it can be
tricky knowing when to start introducing nutrients again.

The only other thing I can think of is your water - Just make sure the water source is also growing other kinds of healty plants too.

Thanks for the insight, I was overfeeding them last week but then I switched to water & calmag only until some new growth started coming in that was really pale green and then I started weak nutes... maybe too soon. I'll just give em water with calmag until they really start looking like they are starving and see if that helps.

Looks like it has an nutrient lock up and over watering. I can see the leaves cupping upwards stating too much water and the brown spots could be Mag Def due to the lock up of nutrients