I have black sand also and what I do is just take my python and kinda hover over the top of it not getting to close to stir it up much! What kinda filter do u have? I have a fx5 and a hob, I have a piece of a panythose cut and placed over the intake. The sand will destroy the impellers. Also every once in a while ill take my finger and slowly run it thru the sand to let any gas build up escape.