The Ink that get used by your canon pro-1000 goes to this tank, so that keeps the heads of your printer clean. Depends on how much prints you make, it is better to have a spare on hand just in case. The printer will let you know anyway that it’s time to replace it. Due to its cheap price, I got 4 extra, when 1 is already in my new printer. It’s all great. You can check “ Rusty Nelson” or “ Jose Rodriguez “ on YouTube on how it is easy to replace them.