The smaller the tank the harder it is to keep balanced . Its new so algae will come easily , as the tank matures it will get easier.
A "little" kno3 and traces only on Sunday Im sure are not helping. Your moss will like it better in tiny amounts more frequently then once a week on Sunday. Also, CO2 ... is that the diffuser in the corner ? I see no bubble in it...check your ph before and after CO2 to see the effects its having , the ph should change.
Give the tank a little time , manually clean the algae, and add 1mm of traces every other day instead of just once a week and see what happens. Also test your NO3, that should be kept up for the moss. I'll bet there isnt much left there by the end of a week's period.