I agree, cut down on your lighting cycle for about a week and then slowly bring it back to what you want it to be. Lets say right now you have it on for 10 hours a day, cut that to 6 and then this weekend change it to 8 and then next weekend change it to 10 and you should be good to go. These are diatoms and are quite common with new tanks, but also come about whenever lighting is upgraded. Should go away without adding anything, so I wouldn't worry to much.