Tandem pump users

How much MINIMUM insulin is needed to fill tandem t: slim pump ? Is 150 units enough?

I used to put 80 units in. You need at least 50 for it to work with filling the tubing etc. it’s a crazy system the way the tubing is filled. Now I do 120-140. So yes 150 is good. When I put 80 in it was not enough with any errrors to fill the tubing I think. So your syringe needs at least 100 to start.


@sweetgal88 Tandem suggests adding ~45 units to the quantity of Insulin you want to use. Their breakdown is ~ 30 units for priming and ~ 15 units of unusable (inaccessible) insulin.

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I had a “blonde moment” while changing my last cartridge. I accidentally told it to proceed with the old/empty cartridge still in place. After completing the process, it gave me an error screen and told me there must be at least forty units left in the cartridge after fill.

So, 40 units plus the 12 it takes me to fill the tubing, and I would guestimate 52 units as being the minimum fill value.


I am guessing their 30 units for priming was assuming 43 inch tubing and luer lock connector. With the 23" tubing and the t-lock connector, we are only using 11~13 units for the prime.

Same here.