I just performed a deep clean on my Triton ii 60 and the sand bed was a few inches below the intake port. I believe that is too low--only half way, and I should add some more. Anyone familiar with this filter to know where 325lbs hits? The intake port is right before the bend back in, so I'm curious if that should be at least partially in the sand? I can't find a spec sheet to say exactly how far from the top. Thanks.