Yeah it's not perlite. I couldn't see the green you were talking about. Had closer look. I agree after reading nobodysbuds/mouse, just algee it happens in nutes in bottles that are exposed to light. Wrap some black tape or a wrap that covers it up, no light, no more algee. Sry bout bad question i dont read others replys, i just couldnt see it. If id of read and looked proper id of seen it. Best of luck.