How to tween a part to only resize up and not down?

Help and Feedback Scripting Support
1

Hello, I am creating this game where u can collect blood into a jar and the jar fills up. However when I am creating it the blood in the jar resizes itself both ways here’s a example:

The tween is on loop so I can test it however the blood is positioned at the bottom of the bottle and resized on the Y-Axis to the lowest part.

Heres the script:

TweenService:Create(EmptyVial.Handle.JarLiquid, TweenInfo.new(1, Enum.EasingStyle.Linear, Enum.EasingDirection.Out, -1), {Size = Vector3.new(Blood.Size.X, 0.523, Blood.Size.Z)}):Play()

I was wondering if there’s a fix for this as I want it to look like this:

2

It will resize in both directions, as it will always maintain the exact same position when changing size.
You’d have to calculate the full size of the blood mesh, and divide the Y portion by two, when growing, move the position up its full size, by saying Size.Y/2, and if its deprectating, move it down by Size.Y/2 to its empty size.