Doing a biotope is fine, but I recomend you start by researching specific fish you would like to house from the carribean, and then come to a conclusion as to what system they need to live happily and healthy for their natural life.
Good old Doctor's Foster and Smith! LOL. Here is a quick search I have done on their website for fish from the Caribbean.
A 10 gallon is going to be limiting to stocking choice, and whilst "do-able" its not going to allow you to keep much in the way of fish. Probably two to three.
As said, there are many fish in the carribean, so its going to be near impossible for anyone to ramble on about every fish found there. Personally, id buy two or three neon Goby's, and that would be the stocking capability, then, if your lighting suited, add some corals like mushrooms and Zoanthids.
For general marine up-keep, I sugest you read
this thread and buy a recently published book. This gives you insight as to how to keep a marine system.
In the marine world, there is alot more persnality than in FW tanks, having had both myself previously.