Here is a test render in arnold that I did to see if the lighting would work with other elements, and to see how rendering a sequence on my computer would go. This shot took over 24 hours to render at 720p so I'll have to rely on render farms which is what I was expecting anyway.
However I like how this lighting bounces off the moving elements, it still needs to be tweaked and I would like the caustics to vary a bit more, but overall I like the look. I also have to change the samples as everything is a bit grainy. Also I need to figure out the skydome lighting, as my matte painting is blocking out light and casting on my scene, however since my animation has elements that are transparent and reflect and refract the matte painting, it is not easy to add it in later as layering would only work so far when it comes to tentacles and the jellyfish body. This layering effect would work with my bubbles as I could 'screen' them over the top, but the whole jellyfish cannot have the same effect. At the moment I am trying to disconnect the matte painting from the main skydome, and give the matte painting its own separate light.