I believe aero systems grow different roots than DWC type systems. you probably gave it too much light too quickly. The plants hadn't converted their root system yet and thus couldn't provide as much water as the leaves transpired.
Well . . That's just my immediate thoughts on it.

should i start them off in the auroponic kit first then. would that be the right way to go about it? the roots are just now starting through the rockwool cubes on the ones that lived. i'm using 1 inch cubes. the ph is at 6.2. i have checked everything so far. i started another 8 sets of seeds today. i might just try them in the auroponic set up first this time. i started them under a 150 watt hps. these i'll start under the bigger lights. do you think that will help this time?

I think grizzman hit the nail on the head. Further, I suggest you not grow tomatoes and peppers together.

The reason for this is that one is a heavy nitrogen feeder (tomato) and the other is not necessarily (depending on particular cultivar, I'm sure).

Nonetheless, it's been my experience that while each like a slightly more acid medium 5.5 to 6.2 pH, it's hard to maintain both that and a feeding schedule that is useful to each. I'd grow them in separate systems.

I think how you're starting them is fine. When you put them in your aero system, try giving them diffused light or indirect sunlight for a few days to give them time to adapt.
Very similar to hardening off vegetable seedlings to be grown in the dirt.

here's a update. i replanted more seeds and let them get up pretty well with roots coming out of the rockwool this time. i moved them from the bubbleponics sprouter and into the auroponic set up. when i went down and looked at them today they are taking off like a house on fire now. plenty of roots and growing great. maybe i did move them to fast last time amd this time i have lost none at all.