[poodlebone]

I use Minimed, not Animas. I use room temperature insulin and try to draw it into the reservoir slowly. I tap the reservoir to collect any air bubbles and push them out before connecting my tubing. Everything may look perfect but the following day I see some bubbles. I've read that it's because once you have the reservoir/cartridge in the pump it warms up a little more (even if it was room temp to start with) and that causes more air to come out of the insulin. Depending on what I see I either leave it alone or I rewind my pump, tap all of the bubbles together and purge them out of the reservoir and then prime it all over again. That usually fixes it for the rest of the life of the reservoir, which I continue to use until it's empty.

If your reservoir looks bubble free when you first start it and you see the bubbles appear later, you may just have to deal with purging them. It's not a defect in the cartridge or the pump.