hi I brought a santa monica 1.3g algae scrubber and its been almost 1 month im just seeing small little dots. I emailed santa monica and they tell me to cover the light more and do 18hr air pump. first it was nothing on the screen but after following santa monica 18 hr air pump now I see little black dot on the screen. im I doing something wrong? another question is the cover suppose to fill up with water or the top part is filled with air? when I check my algae scrubber I see that my top part isn't filled with water