[Aardil]

Brians256,
No it is not silent, pretty close but not completely silent.
I do hear a bit of hum from the A/C unit but it is muffled down a good bit with the channels and the undercoat. I do have one of my older pumps that "rattles" it has been that way for a long time but keeps pumping. I can hear it rattling when the compressor kicks off. The new pumps ( i have read ) have a hi pitched whine when run at max setting. I cannot hear any of this "whine" again I believe do to the undercoating acting as a silencer.

If you look at the pics on page 3, the Pics "all filled up" you can see the old fill tube on the left hand side of desk. this is what did not work.
If you look at page 3 the pic "Fill point". that is the fix.
I had to cut off the old fill pipe, cap it and drill a new fill point, this one in the top of the rez.
The old fill point was a 32" long hoizontal run to the rez. with all 4 pumps running the air could not make it back to the fill point before it was sucked back into the system.
For the initial bleed ( when it was not in place) I could and did get the air out by elevating one side of the bottom box about 12". that gave the air a way to get back to the fill point.
after I set it in place elevating one side was impossible ( too tight of a fit ), all looked good until I started connecting up the water blocks inside the PC's.
Air was introduced at that point and no mater what I tried I couldnt get the air to bleed out. I probably could have gotten the air out doing one pump at a time and letting it set for an hour or so, then bleed some more. once one was bled, then move on to the next system.
I fought this battle for a full day before deciding that a fill point into the top of the rez was a better plan. after I got the new fill point installed the whole system ( all 4 pumps) bled out within 30 minutes