ive had my aquarium up for about a month and a half now...there were a few brown spots on one of the rocks when i first got it...now it seems as if they are spreading like wild fire...not only to to other rocks...but now to plants and the gravel...i put my hand in and it rubbed off a plant. Seemed kind of dusty. Could it be the rock just like falling apart or is it some sort of bacteria or fungus??
//edit *added some images
the rock where it started
spreading to another rock
normal gravel
gravel where the brown stuff has spread
normal plant
plant with brown stuff
//edit *added some images
the rock where it started
spreading to another rock
normal gravel
gravel where the brown stuff has spread
normal plant
plant with brown stuff