I started my tomato seedlings under indoor plant lights this year, since last year's got kind of leggy just sitting in the window. However, they've not been very successful. The leaves are distinctly yellow, the growth seems sunted and the some seedlings have completely died. See the attached picture for a fairly typical specimen. Its the area between the veins that seems to yellow first, and some of the plants that died were almost completely yellow, almost white, at the end.

Inititally they were in one of those plug trays with a heating mat under it, and a plastic trasparent lid, with the lights almost touching the lid. Once they were all up and the first true leaves were beginning to grow, I took the lid off and lifted the lights up bit by bit to try to stay ahead of the plants - they may have touched at times, though. Once they had a few leaves I moved them on into 4x4 pots as shown. It was after I potted them on they seemed to get worse, although they were definitely affected before too.

I sort of think maybe I've been overwatering them. Although the water hasn't been that frequent, they do seem kind of damp, and the one that seems driest does not seem affected. I thought maybe it was a nutreint deficiency (they're in peat and perlite with no fertilizer), but giving them some very dilute maxsea didn't seem to make much difference. I wonder if the spectrum of the lights is wrong (they're plant & aquarium bulbs from home depot and seem kind of orangeish) , but the peppers and eggplant under the same lights seem fine.

Any thoughts?

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