Particle Flow Toolbox#2 setup for cloth/water interaction.
Water is simulated super lowres with Particle Flow Toolbox#2 that controls the cloth setup as well. the water is then emitted from the few Rigid Body Particles in Glu3D to. The test in higher res should give an impression of filling and stretching the bag under the weight of the water.
Inspired by the tests by Ron Fedkiw:
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