Test loop safe?

[BWR]

So I needed to test my pump to see if there were any defects so I could RMA it if it had any. Well my test loop came out to be Pump -> Res -> Pump. The thing I am worried about is that the water in the reservoir was moving so fast that it was creating bubbles when hitting the reservoir's walls. The less water, the more bubbles. Too much water and bubbles will still come. When bubbles
start to form they are pulled into the pump and the pump starts to make a sound like tiny bits of sand in a plastic container thats being shaken. Is this considered 'bad' for the pump? If it is, should I just add more 'restriction' (like a block or a rad) to the loop to prevent the strong current that makes the bubbles?

Another thing is that the bottom of the pump gets fairly-very hot after a few minutes of use (<10 minutes). Is there something wrong with the pump?

And to show off my 8 mega pixel camera...
http://img132.imageshack.us/img132/5591/dsc009862ik.th.jpg (http://img132.imageshack.us/my.php?image=dsc009862ik.jpg)
The test loop (full resolution)

http://img132.imageshack.us/img132/5351/dsc009854si.th.jpg (http://img132.imageshack.us/my.php?image=dsc009854si.jpg)
Test loop with Yate farm to keep the PSU under load (cropped to make it smaller)

Pictures are somewhat compressed by Paint.

[warriorpoet]

The pump is generally cooled by the rad.

Also, there is no point to running a test loop without everything installed.

[ReD.SkY]

its fine

[BWR]

The pump is generally cooled by the rad.

Also, there is no point to running a test loop without everything installed.
How would having everything installed help me if I only want to see if the pump is working? This is not a leak test.