My betta Zach likes movement. If something outside his aquarium moves, he's at the glass watching. So I was thinking about (I might not do this, just getting some ideas) a tank mate for him. Something like shrimp or such. Not another fish, please. He is in a five gallon tank with black diamond 20/40 grit as substrate, a dwarf chain sword, and two Marimo moss balls. He has a submerged power filter. I plan on getting a java fern, Anubias nana, and a cholla log with Marimo moss grown on it.