The green "moss" on the flats is probably algae. It shouldn't harm the seedlings except that it competes for the soil nutrients and tends to keep the soil surface from drying out properly. Algae is usually caused by the soil being too wet (which is pretty common when using peat-based mixes).

I've included a link (below) that should be helpful.

Art

Here is a link that might be useful: Algae

Agree. Too wet and not enough air circulation. Cutting back on watering and using a small fan to increase air circ solves the problem.

As to using the domes - not a direct cause of the alage, too wet soil under the dome was. But not using them to begin with is a definite plus. If used they MUST be removed as soon as the plants even begin to break the soil surface.

The darn advertisers that show all these pics of plants happily growing under the domes do gardeners a real dis-service.

Dave

I think a large part of the difference between your success and your wife's problems, is related to the fact you are growing seeds that germinate in three days, while hers takes three weeks. Al