getting green algae on soil surface in humidity dome

hey guys, I have a couple seeds that cracked a week ago and have been in my dome ever since. While in the dome, the water in the soil doesn't seem to evaporate at all and has left some green algae growth on the soil's surface. is there a way to avoid this, is this a sign of my having too much water in the medium?

I never use a humidity dome to be honest with you. I germ my seeds and then transfer over to a root cube and place under a CFL in open air. It sounds like your humidity is really high, so I would make sure to clean the dome almost daily if you are going to keep using it.

I never use any sort of "dome" either... Straight from the moist paper towel on a butter plate, to the perlite and peat moss-rich soil, and never have any algae problems at all... The only "dome" I ever use is a large plastic bag over my germination plate, before they pop their taproots out, just to keep my water from evaporating away if I forget to check them every single day during the process, as I am more consumed with my flowering and vegging beauties, and do more cloning than seed-popping...