Bekah, your grandparents must live in a rather cool area. Around here trout stocked in ponds don't last the summer. It gets too hot for them. They stock rainbows in the streams, tho. Well some of them.
Sakura, a lot of the darters and pygmy sunfish do need live. But there are some hardy and pretty darters. The one I pictured is one of them. Unfortunately they aren't found this far north. But there are a lot of pretty minnows, and those are easy.
Beautiful guppies, copper! I like livebearers, but I've never been a fan of guppies. Most of them seem too gaudy especially with huge tails, but yours are beautiful. I'd like to have a tank of endlers one day. Preferably N class.