Can different a few different types of apistos with maybe a Bolivian Ram? I'd only keep one of each species because they can get more aggressive when raising fry and also I don't want fry. Would i have to worry about apsitos hybridizing or would they not? I guess i could just get all same sex so they couldn't breed. Assuming I'd use lots of tall plants like amazon swords to break their line of sight, how many square feet of territory does an apisto or ram need to stop aggression???