No they don't need heaters. Anything above 78 degrees can kill them. I had ghost shrimp that died at 81 and they're native to North America where we have winters and are found in area than can reach below 32 degrees. And I hear they don't need bubblers. You could add some live plants to oxygenate the water and to help remove excess nutrients. I'd add a bubbler if you don't add live plants... Hope this helps