Leaking MPM solver

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Hi - any tips on keeping MPM solver from messing up collisions? I've got some viscous/sticky fluids inside a sealed collider, using the vdb/invert option in the MPM collider node. The simulation always has leaks/errors, it looks like the sim is lagging the animation and this allows the edge particles to escape. See vid attached

Things I've tried:
1. substeps - min/max up to 200/20000
2. CFL - down to 0.01
3. looser/denser meshing for the collider
4. changing collision type to animated deforming (instead of animated/rigid)

Thanks for any advice! Chris

Attachments:
liquiType.[0001-0128]_1.mp4 (8.5 MB)

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Fixed! By watching the MPM masterclass, which is super-helpful by the way.
The missing checkbox was this one, which watches out for particles creeping through the collider, exactly what I wanted.

Attachments:
mpm_collisions.jpg (59.3 KB)

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Can't remember the issue I had, but was puzzled as to how to change it when I was doing some metal mpm sims.
Putting this setting on helped a lot and gave a much better result.

The only difference in my case, being metal, it worked better with the drop down set to 'Position-Based Move Outside Colliders'
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