Spotted, dying leaves on very small plants

These plants have been growing for over a month now, and they're barely making any progress. I'm not sure what to make of it. I have them under two 80-watt 48" fluorescent fixtures with daylight spectrum bulbs. At first they were under one, but I doubled it. They're in good garden dirt that I grew outdoor plants in earlier this year. I haven't been watering them much although when I first planted them the soil was fairly wet. I've seen this problem in two other grows. I have a few very young plants that don't seem to be affected - yet. All my plants are growing slower than I'd expect. I added a very small amount of fertilizer to about half the plants but it doesn't seem to have made a difference in whether they have this problem. I measured the pH by slowly adding water to two of my worse plants until water dripped out the bottom. Pretty much 7.0 exactly, maybe a little less. Any ideas? Thanks in advance.

A pH of 7.0 in soil is ok but there will eventually be a deficiency in manganese and iron with a pH higher than 6.5 but I dont think thats what we are looking at there.

Generally slow growth to me is a root issue, or things associated with the roots. In this case the soil itself looks a little hardcore for seedlings or clones. You might want to take a look at some potting mix that doesnt have too much bark in it, and isnt clumpy, or, if your plants are really small (cant tell from the pics), even seedling soil mix.

Looks to me like (and this is a wild guess really) the growth has been slow because the roots are having probs in that soil for whatever reason. Also looks like the fertilizer has probably burnt the leaves too.

They're in good garden dirt that I grew outdoor plants in earlier this year.

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What type of plants did you previously grow in the soil outside?