okay so i feel like all i do is is post in emergency all the time so i down graded my 90 to a 75 soaked all equipment in vinegar and cleaned it well, put all water rocks and aragomite that was on the bottom which i rinsed really well rather then replace it, after a week of being in the 75 i have diatom all over the bed and cant seem to get the cpr bakpak to skimm all it wants to do is push bubbles into the tank any help would be great