Not sure if I completely understand your set up but if I do then it sounds like the ppm difference between your reservoirs may be because some salts are being retained in the media you're dripping into. Seedling nute usage is negligible and frankly probably within the margin of error of your meter.

As far as the health of your seedlings it sounds like they may be getting suffocated. Are they in some type of cube like rockwool? If so, it may be too constantly saturated. Temp seems okay. Light seems fine.

I've had seedlings act weird before like you're seeing. Before they should ever need nutes they start showing deficiencies. I have no real proof of it but I think sometimes plants can out grow what their roots can provide or what they can translocate. Well, I guess there is some proof. Read an article on lettuce tip burn recently that stated that too much light causes the plant to grow so quickly that it can't move the calcium fast enough hence tip burn. It's not a calcium concentration issue but a light issue in some cases. Anyway, I digress.

I see it's been a couple days since you posted. How are they looking now?

Things have gotten better since I dried the cube. They are looking more green. The main issue now is the first set of true leaves seems to not be forming right, instead of actual leaves their just forming small purple microleaves which are curled down. How do you think they look?

It looks pretty normal to me, the purple color tends to happen with tomato seedlings, something about the temperature causing them to not be able to take up potassium? It is a normal, and temporary phase. Anyway, they look good to me. If you have 150 watts in a cfl, you will want to keep it close enough to the seedlings to keep them from getting leggy, but not so close it burns them. Hope they do good!

Looks fine. If they started looking better after you dried out the cube they were probably getting suffocated. They just need some time to recover. Keep us updated.

Yeah they look like they are getting better! But, now it's more obvious with the deformity in the first leaves now... What do you think? I mean they are certainly growing but they just dont look right.

That's better. Give it some more time. Those leaves are too small to make any judgement calls. The plants had been stressed so it'll take some time to recover. Most of the time damage that may occur from stress won't fix itself so if the leaves started out funky from being stressed they may look a little weird but it the problem is corrected any new growth should be fine. Hey, they're growing, that's a step forward!

Now you can really see what I mean by the formed curly growth on the right most seedling, the left one seems to be more healthy and I'm leaning towards chopping the right one, so i'll just have 1 main big plant. The leaves are nice and green, still purple although in lesser shades now. They are growing quickly... Something tells me though that 350ppm is way too much for seedlings and I might want to change my water as its 350 parts nutes/220 parts water&ph adjuster(575 total) and maybe if I lower that ppm they might speed up even more, even though they look healthy. I have no idea. The purple stems are just really bugging me and I know I've got their environment dialed in perfectly... As they aren't leggy for light, or any discoloration of leaves, purely just that purple color :/

Res temp: 70

Room temp: 74

Light: 150w inside a small space so it's more intense on a single plant

2 air rocks,

Ph: 5.8

drip dwc recirculating

air flow(although not enough to blow on the stems at all just fresh air)

and those 330 ppm's of nutes... What looks off?

What variety of tomato are these? Some varieties(particularly the ones with ancyanthins(sp?) are much more purple naturally. Is it a variety that is supposed to produce black/brown/purple/ fruits?

Many of mine started out with funky curly leaves, and progressed to normal looking, healthy plants. If you only want one, you could cull the other, but I don't see any reason for concern. I used 500-700 ppm for my tomatoes, and it wasn't too much. They grew quickly, and did well. As for the purple stems, it is just a temporary nutrient uptake issue. As they get older, it will self correct. I have had it in numerous seedlings, and they all grew out of it, and went on to produce very well. If I were you, I wouldn't let the purple color, or the curly first leaves bother me(at least not make a decision to cull because of it), I would keep doing what I am doing, and give them at least another couple of weeks.

Carrie

Looks good!