the problem with the keys is that there is almost no soft coral, which the only kind you can harvest. if your looking for fish on the other hand, i know that just about any healthy section of reef will have a nice assortment of wrasses, angels, tangs, butterflyfishes, and others.
ive been spearfishing out of my house in key largo for the past 2 months and i cant believe how many huge french and queen angels and butterflyfishes i have seen and wanted so bad, but they are usually very large adults. the wrasses on the other hand have been small, usually under 3". i will be researching more on them after i snap some pics and get them id'ed to see if they will be good for a tank. oh and by the way, they all seem to be verryyy curious and easy to approach, so catching them with a net may not be very hard. if it turns out to be, i may invest in a slurp gun