I’m sure other pump users are very used to the routine after you refill your insulin pump and connect a new line to it. Before you connect it to your body you need to flush the air out of the line and prime it with insulin.
We start the prime operation on the pump, and then stop it when all bubbles have been pushed out of the line. But first we need to see where the bubbles are (or where the insulin is up to for a start). I think many people instinctively stretch out the tubing and hold it up against a light while they look along the tubing for the moving insulin/air boundary. But it can be easy to miss, especially if that long stretch of tubing is shaking at all. It is easier to see that boundary with the blue tubing of the Orbit infusion sets, but most tubing is clear.
Here’s a little trick which might make it easier. Using a phone, display a white background and place the tubing on it. An easy way to get a white page is to open the web page about:blank. That’s the actual web address (instead of starting with https://): don’t feed it into a search box!
Coil the tubing up on the screen so you can see all of it at once. This video should illustrate the process:
Note that although my phone is waterproof, I did wipe up that drop of insulin with a tissue rather than let it run onto anything sensitive. You could hang the end of the tubing off the side of the phone of course.
This trick can be used in a dark room: you don’t need bright lighting to prime a pump line!