Apidra is not recommended with this pump, Novolog and Humalog are preferred. Apidra is synthetic and will close a lot of inclusions. I just switched from a Cozmo and Apidra to a TSlim and Humalog. My wife is a Nurse Pract at a Joslin Diabetes Hosp., and is the one that told me about this before I switched pumps. Just a thought!
My diabetes educator for Tandem told me that it is important to use room temperature insulin, because cold insulin holds air. Not sure if that is the problem. Perhaps getting rid of these air bubbles is more important with the T-Slim. Not sure.