You can spawn convicts in a bowl. Not that I would allow it, it COULD be done in something like a 1G jar or something. They'll spawn given any circumstances. But yes, you can spawn them in a 10G. My male was always the wquiet one, no aggressiveness in a 20 high so maybe your's wil be fine also??? Just add lots of caves, plants(live/plastic), rocks, caves etc. No gravel. Or maybe sand. But no gravel allows you to feed the fry better.