Why is my dirt have a Green tint ????

I Have two plants that are only about 10 days old , they are in cups growing under 2 24"
flos and one CFL i have used this set up in the past and never had a problem, anyways
I noticed when i look at the dirt some parts of it have like a green tint to it, it isnt alot
and is only on top so if i mix it a little it goes away . Is this a bad thing what did i do
the tempature is always around 75 to 78 degrees and the humidity is around 30%
any info would be helpful just want to make sure it isnt bad. one plant is growing great and healthy
and the other is growing kinda slow.

Are u letting the soil dry out completely?Do u cultivate the top of your pot every so often

i water about every 3 days and the day after i water i stir the top of the dirt ........also another question i planted both of theys plants the same time and they sprouted the same days,
one has one set of serated leafs and the other is on its set of leafs with 5 fingers whats wrong here. is it a bad plant should i rip it out since it isnt a super female as the other one?
and they are feminized seeds.

Can u upload any pics???

sounds like green mold. I had it once, I was using white styrofoam cups . It didn't kill my plants , I read on another forum I forgot the name of to pour hydrogen peroxide on the roots. I did and it helped. When you repot if your roots are all green and slimy thats what it is for sure. It happens when light gets in your roots and not letting your soil dry out a little.

i have them in styrofoam cups but i have taped the cups up with black electrical tape to keep the light from getting in the cups.