When contaminated Water and normal Water should mix (maybe into contaminated Water?) instead the Liquid Mixture starts to "wobble" and "jump". (I don't know how to discribe it better.)
I attach my savegame in which this is happening. At least at my PC. Look at the waterpool at the bottom of my base. At least on my PC everthing is jumping.
Let contaminated water flow into normal water over an uneven surface (e.g. by removing an obstacle). Add some Liquid from above. Maybe it works, maybe it starts jumping.