I used a T on the suction side of my pump but I could never get the air out. Well two weeks of having to hear the sound of the impeller misbehaving convinced me to build a small inline reservoir that traps air and serves as a filling point. I wish I'd thought of that from the beginning. Here is a pic of my system, with the reservoir in the upper right.
The water is slightly redish from the added Water Wetter. The brighter, thicker hose is silicon, the rest is PVC - i plan to replace the PVC with silicon some time.
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Pump:Eheim 1048,
Radiator:LPD radiator 100x150x20mm,
CPU block:DD Maze-2,
GPU block: DD GPU block,
Chipset block:Zalman NB32
AMD XP 1500+, EpoX 8K7A, PoV GF3Ti200
Pic of my YY-cube