Neem oil?

I know this is "technically" not a seed germination question, but it is about my seed starts. My propogation units have issues with algae, and usually just about the time they really get going the boxelders come out in force. To make matters worse, some of the plants I brought in over the winter evidently had aphids, so now I have an infestation to clear up before I can start my seeds.

My question is, does anyone use Neem oil as a insecticide, and does it help with damping off and/or algae? Should I just spray it on the top of the flats after I sow the seeds, or do I wait until the seedlings come up? Can it hurt my baby seedlings? I read that it is a great natural insecticide/miticide/fungicide, so I was just wondering if anyone uses it and whether it is any good.

I would use the Neem as an insecticide on plants that have bugs on them, and I would use hydrogen perioxide mixed with water for the algae and the soil that the seeds have already germinated in-i.e-once they start to have roots.
You can bleach your propagation units before you use them, and make sure that you rinse them well. Not sure what they look like but I assume that you can soak them in bleach/water solution or use bleach/water solution to scrub them?

I usually clean them up as best I can, then run them through a sani-rinse in the dishwasher to sterilize them and let them air dry. Seems to work pretty well - at least I have avoided the dreaded damping off so far.

I have a couple of different types, some from Lee Valley and some from Gardener's Supply.

I haven't had terribly good luck using neem to control fungus--it works fine on insects but for fungus I've had better luck using hydrogen peroxide. (although for aphids, I've found insecticidal soap works just as well and smells better than the neem...so I save the neem for tougher things like scale)