whats this stuff

[cluster]

i got liek white dusty looking suff all over my plants and the dome in the tank i dont remeber it being in my last fish tank if this is a retarted question sorry but im getting started aand as i go on ill stop being annoying just wondering whats going on \

 

[Dubby]

Are you in a hardwater area? It could be limescale buildup esp if it is on the dome as well.