Digital BW, The Print

Mark is absolutley correct.

The bottles must be placed no higher than 4" below the print heads 
and no lower than the base of the printer. Also even more important, 
the lines must NOT sag when they leave the 7000 cartridges. Self 
adhesive backed hooks to hold the lines parallel will keep gravity 
from pulling the ink from the heads and letting air get in.

I have now had these parameters on my CIS for about a month and I 
have had no air infiltration. Also, it is important to make sure that 
all connection within the CIS, that is tubing connections must be 
sealed with silicone.

Mike