I just dealt with a Tang and HLLE. It was brought to my attention that carbon dust could remain even though the GAC has been removed. The last place I see this as possible is in the refugium where I have a layer of sand and then a layer or Miracle Mud under the top layer of Matrix. I want to vacuum the fug to remove any carbon dust. I would remove the Matrix by hand to put back in but then shopvac out the sand and mud permanently. Then return the Matrix. Is there any negatives to removing the sand and mud? Could these two layers contain enough bacteria to crash anything considering the Matrix and DT sand and rock? Thank you.


