Animating scale of particle objects?

I’m working on a few various little test animations for a bigger project and I’m having some trouble with a particle simulation. The effect is supposed to be kind of a black goo rising like fire off of the character’s body, using a metaball as the particle object. The problem is the particles just kind of disappear and it looks terrible Is there any way to animate the scale of the metaball and apply that to each new particle spawned? I know Ive managed this somehow a long time ago but for the life of me I cant remember how.

Here’s a VERY basic render of the set up
[video]https://youtu.be/JMu_MQXGh6c[/video]

Use a particle texture to control the size of the particle over the particle lifetime

See attached example

Attachments

particle_size.blend (336 KB)

Awesome exactly what I need