I can take it easy in a bit(like 3-4 hours when I can actually eat some food :')). In the mean time, a fishy. The pike killifish. It's native to central America but it's a relative of guppies and not the large pikes to which it's named after. https://en.wikipedia.org/wiki/Pike_topminnow
They're apparently quite fierce little predators and not so popular to keep because they eat a lot. Since they're a kind of guppy they give live birth too. I imagine if things went right that they could overtake pikes and other large predatory fish like gar. Those niches just have to be made open is all. They are invasive in Florida too, so they do have the ability to spread out fast.