Well, my goal is for fish to have the best care possible. So, if it were up to me, I would tell the kids they have to wait. You can still get catfish a few weeks from now. But the danios and tetras won't appreciate being in groups of two for that long.

By the way, with 6 Zebra Danios, 6 Golden Danios, 6 Flame Tetras, and the pencilfish, you are pretty much stocked, but you could have 3 Cories with them. I can't blame your kids for being so excited about the Cories--they are so awesome. Always wanted some myself. Well, have fun with your fishies!