the flordia fish and wildlife conservation says that arowana's cant survive tempetures under 59 degrees. Thats why there not a prohibited speices. But all other speices that fall under the bony-tounge catagory are strictly prohibited (like the pirariu. or however u spell it)
Oscars are classifies as non-native
I can go behind my house, walk 20 yards, throw a cast net and pull in about 20 brown hoplos each cast. There everywhere. There supposed to be from trinidad. (strictly prohibited) You can be fined if you release them back into the water. (i guess i could be fined on a daily basis)
I also can catch freshwater flounders. I keep about 6 in my aqaurium.