# Filling TSlim cartridge **URL:** \ **Category:** T1D Tech & Daily Management Support\ **Created:** [June 23, 2024, 2:15pm UTC](https://forum.breakthrought1d.org/t/filling-tslim-cartridge/74094 "2024-06-23T14:15:56Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![edmundo](https://avatars.discourse-cdn.com/v4/letter/e/e5b9ba/32.png) [@edmundo](https://forum.breakthrought1d.org/u/edmundo)\ **Post date:** [June 23, 2024, 2:15pm UTC](https://forum.breakthrought1d.org/t/filling-tslim-cartridge/74094/1 "2024-06-23T14:15:56Z")
I use 80-90 units of Novolog daily. In order to get 3+ days out of my cartridge and infusion set, I try to get close to 300 units of insulin in the cartridge. I always take the insulin out of the fridge and try to remove the air from the cartridge. I use the filling device to aid in filling the cartridge. Occasionally, while filling, I notice a drop or two of insulin coming out of the bottom of the cartridge. Is that possible? Thanks, Ed ---
**Author:** ![wadawabbit](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.breakthrought1d.org/wadawabbit/32/3890_2.png) [@wadawabbit](https://forum.breakthrought1d.org/u/wadawabbit)\ **Post date:** [June 23, 2024, 10:55pm UTC](https://forum.breakthrought1d.org/t/filling-tslim-cartridge/74094/2 "2024-06-23T22:55:49Z")
Hi @edmundo . It’s been a while since I’ve used Tandem so I don’t want to weigh in here but I did want to suggest you call their tech support line. They can let you know if that’s normal. ---
**Author:** ![Dennis](https://sea1.discourse-cdn.com/flex025/user_avatar/forum.breakthrought1d.org/dennis/32/5527_2.png) [@Dennis](https://forum.breakthrought1d.org/u/Dennis)\ **Post date:** [June 26, 2024, 8:00pm UTC](https://forum.breakthrought1d.org/t/filling-tslim-cartridge/74094/3 "2024-06-26T20:00:09Z")
Ed @edmundo, the only time I put 250 units in a cartridge was a week when I was traveling and would have several flight changes - as I remember the cartridge lasted through 3 infusion changes; I usually use the minimum fill which lasts 3+ days. Having taken apart the cartridge, I can’t figure out how it could leak and remain integral. Tandem Technical should be your source on this.