How do you check?

Ok, just want to make sure, are there any good ways to check to see if your system is completely free of micro-bubbles/big bubbles?

So far, I turned the system side to side to make sure that there arn't any big bubbles floating around, and turned the pump on and off to make sure that I don't see any white fluid running.

Also, can implellers cause bubbles?

impellers can't really create bubbles but they can trap them. on my danner 3, you have to turn the pump on and off to get all the bubbles out after filling. but you can hear the air inside the pump so it's not really a mystery wether or not air is in there. as far as making sure that micro bubbles are out, i'm not sure. i guess just use an air trap design.

Well I made sure that my T-line is at the highest point by securing to a wall... it took about a day and a half and I don't see any micro bubbles forming anymore but I just want to make sure...

What kind of noise does the pump make when air is going through it?

hmmm... it's like a churning sound... i guess. but you'll know when all the air is out, the pump just hums; there's no other noises.

Beside the slight vibration of the impeller(combined with a low hummmm) I hear some squeak squeak noise once in a while... Im assuming thats air going through the pump... Ill let it bleed more