is is dynamic or just a texture animation ?
if it is dynimic, caching should be yes a solution to fix that, that's the first thing to try.
if tit is texture, (or dynamic to) it could came from your scale of the container. the fluid id not enought dense to be seen
try to increase the resolution of the grid and/or the density of the fluid...
if nothing work, restart your cantainer from scratch a check at every step if it is okay, it the problem comme again, you ill know when and what to change
let us know
Jaz