It's not a big deal. You can mist the top of the cube with a 1% hydrogen peroxide solution to deter the algae.

you needn't worry too much about surface algae. One fix for both that algae and the fungus gnats is to cover the medium with something like aluminum foil. it will block light to kill the algae and smother any gnats that may hatch.

Awesome i was going to use some Kydex i have laying around the house will that work?

Well i am not sure what happened but the Algae stuff that was there is all gone. Well at least it looks like it is i had little greyish green stuff floating all around in it yesterday now i get off work today and the whole tank is clear doesn't seem to be anything floating around at all can it just disappear like that or was i just mistaken?

it doesn't usually disappear but may have broken up to be less obvious. also, it may have gotten stuck somewhere out of sight like in a pipe or in your medium.

well i got to looking and the algae had settled on my heater in my water and on my thermometer.

Algae is ubiquitous and you can control it but not eliminate it.
Hydrogen peroxide helps control it.