My daughter and I started to finally stock our tank with some community/peaceful fish after about a month of having just shrimp, and snails (unintentionally with the snails, but we've grown to enjoy watching them). We brought home 6 neon tetras, and then a day later we brought home 4 fancy guppies (2 females 2 males) and then 1 day later (yesterday) we brought home 3 leopard guppies (2 females 1 male)

Today, I'm unable to find 3 of the neon tetras -- I've check the top to see if any were floating, and among the plants and such but I don't see any sign of them!

Any tips or advice?