As requested. They've stopped being crazy explorers and now hang out in a pack midway up the tank at the front. So far there's no nipping going on. I know it's possible since I have no girls. I think they're siblings. They were in the tank together with platys and they were the only 4 guppies, so they're well known to each other already and they school really nicely. They're fiercely adorable. I think I'll name them after the 4 Musketeers. Athos, Porthos, Aramis, and d'Artagnan! I love that old movie. :D
I was going to go with Dwarf Gourami but I read about possible aggression despite the fact that they're supposed to be more mellow. The corys are so happy now, I don't want to mess that up. I never used to see them and now they're all over the place. I didn't realize how badly Tango was intimidating them.
So... pics and a video of the guppies AND my huge cory girls and lil boys: