They are awesome! They are always moving (except from 10 pm to 5 am), super hardy, are pretty bold, and extremely easy in terms of maintenance. I have 6 normal one in a heated tank with guppies, a bristlenose, and a semi aquatic frog and 20-24 golds in an unheated tank by themselves. All of the fish do great in both tanks even my one with a deformed spine resulting in his back half always sinking when he stops swimming. But they are by far my favorite small fish species that I keep and my favorite to watch besides my goldfish.