If you want a good answer to this you need to give us a lot more info. What are the seeds growing in? What type of compost? How much light? How much water etc etc?

However, the fact that they have grown for about a week and then collapsed, 99 times out of a hundred is "damping off". This is a generic term used to describe bacterial/ fungal infection caused by stagnant, infected compost. Sterilize the compost before sowing by baking for 2-3 minutes in the microwave and water with tap water. Sow in good light and with good ventilation. Good luck.

It doesn't even have to be 'infected' potting soil for one of the ubiquitous 'damping off' disorders to take hold. A poorly drained, mucky potting mix is often part of the problem. So is too much moisture. If your seedlings are not getting enough light, the stems will be leggy and spindly, with weak cell walls.

As ifraser says, it will be very difficult for anyone to help you without knowing a lot more information. YOU have to help us before we can steer you in the right direction.

Why are there 3 postings of this same question, all dated the same day, yet no replies to any of the requests for more information?

If you can't see your post after you post it the first time then you need to refresh the page. There is no need to keep posting the same question over and over.

Dave

See: http://forums2.gardenweb.com/forums/load/seed/msg052019442057.html?1

http://forums2.gardenweb.com/forums/load/seed/msg0520143831049.html?1