Hey Doo-E,
I think you need to look up the behaviors of the animals before buying any of them. For example, Clownfish will not generally tolerate being in 3's. Once the two dominate ones pair up, there is a high possibility that they will kill off the 3rd.
Also, you have a lot of burrowing animals for such a small tank. You will most likely see aggression issues. If I were you, I would take you list of fish (all 10), cut that in half (to 5) then cut the remaining list down to 4.
I would also rethink about the Pistol. I have had one and they dig...everywhere...all the time. You will never see it (only hear it) and you will need to support your rockwork somehow. My Pistol has collasped my rockwork several times.
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32"x32"x20" Cube-ish tank
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