helo ID and fixing

[ClownFish664]

Images below, can someone ID and help me resolve this algae issue I am encountering? Once ID'd what does it feed off?

 

[Dolphins18]

Diatoms. Very normal in new tanks. They will go away in time, snails help speed things up.

 

[ClownFish664]

Diatoms. Very normal in new tanks. They will go away in time, snails help speed things up.

Diatoms at that length? Also won't come off the rock unless a use a brush