need help with my incubator..First time incubating.

[Britt23]

Okay so this is my first time incubating chicken eggs and I did a lot of research before going forth with this, but I was wondering how to reduce or prevent bacterial infection. I candled my eggs and one seemed to have a lot of spots and I read that could be bad. The rest looked okay, I think, I saw a black mass near the end of the egg indicating an air sac. Also should I try using a lower watt bulb? I am using a 40 watt and having a hard time managing the temp and humidity. I have my eggs in an aquarium with a bunch of water bowl and I am covering the lid with like flimsy cardboard/plywood. I keep trying to adjust the gap to regulate each, but it is hard.

 

[sumi]

When the hen lay an egg she covers it with a "bloom" which helps prevent bacteria from entering the egg. Hatching eggs should therefore not be washed before incubation. Other than that I don't know what you can do, except keep your incubator sterile and only handle the eggs with clean hands.
If you could post pics of you incubator we may be able to advice you on temp and humidity control.