The wonderful fish are certainly there.
The coral in the tank cannot be customized. But the fish certainly can be changed to suit your preferences. All the things you see are hard coded into the program and must remain so to maintain realism so that fish aren't swimming through each other and the corals. But, Jim is working on a new version right now that will be about 2x the size of this tank and all in true 3D just like the fish. Stay tuned for that one.
As for the starfish, it will certainly crawl across the glass, but it does it in its own time. However you must leave the lighting set to random for this to happen.
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