This looks great! The only thing that triggers my OCD are caustics below the (anti)Hero fish. It's cool effect and I understand that you wanted to make it visible but, for me, it's kinda upside-down. Maybe it would function better if it would be more subtle.
I mean, such strong light could come only from above and not below. ...and there is more surface on below to express the effect. I understand. I guess :)