Yeah, a 9 meter diameter one, which adds mass and volume and complexity and detracts from the payload.

Instead what they do is use thrust to accelerate the whole vehicle a little, which presses all the liquid into one end of its tank where it can be pumped out. Instead of carrying special settling thrusters, they originally planned to use ullage gas for this but it's not clear that can work.

deeper discussion with math: https://forum.nasaspaceflight.com/index.php?topic=60124.60