* Thunder is a Lince Cat by the way - woof!
Upper level fish for me would be Festivums, Heros, Angels, or could go for characins, Myleus, Metynis, Triportheus and for good measure a shoal of small tetras for that really natural look. They will be to small for Thunder to hunt, you might lose a few to the Geo's but it would look the dogs dangleys......