Aquarist opinions needed for an ecocolumn project?

In reality, most fish will survive the month or so the project goes on-- I've seen it. However, there is a level or morality you have to set yourself before attempting this. It is the equivalent of putting a German Shepherd in a crate for a month and giving it food sparingly. Your best choice would be a small species of freshwater shrimp (Ghost, Cherry, etc.) or snail (Ramshorn, Malaysian Trumpet, Pond, etc.). I have seen Goldfish survive, but they fail to live their full lives (15+ years) after this experience. Bettas may work (you'll need air holes), but they are very prone to infections and often end up rotting, destroying the whole project. Something like Java Moss, Hornwort, Water Sprite, or Anacharis/Elodea would be the best choices, along with small aquatic invertebrates (shrimp or snails), and this will give you a better chace of success.