Sounds like bugs!

Karen,

I don't think the green moss/algae chewed off the tops of your peppers. The green stuff is common. I get it fairly frequently and I combat it by "cultivating" with a small rather pointed tool (sometimes a toothpick). The fan and watering from below should discourage a recurrence. If left unchecked, the green moss can rob your seedlings of needed nutrients.

I agree with jwmeyer that some kind of insect seems a likely culprit. You might want to pour out the container that suffered the damage and go through the growing medium looking for some creature that might eat tender young pepper plants. Just to solve the mystery.

I routinely treat my indoor growing medium with a little bacillus thuringiensis to control fungus gnats. That might help in your case.

MM

MM
Thanks for the tip using toothpicks, last night I cleaned off the slime using toothpicks, cultivating at the same time and I was surprised at how compact the potting soil had become. Also, I was also surprised that although the soil "seemed" moist it was actually dry, I will be watching the soil moisture more closely and not over watering. I had been putting too much water in at once and not keeping close enough watch on when it actually did dry. I think over watering may have stimulated the slime too.

Karen,

If you have small electric fans going to create a breeze for your seedlings, the air circulation tends to dry out the surface of your growing medium and discourage the growth of the green stuff. The seedlings also get some "exercise" in the breeze, which helps them to grow thicker, sturdier stems on stockier plants.

MM

Caught my culprit eating the seedlings...a mouse!! No more chewed seedlings.