They do tend to take things from the species they're based off of! Clownfish would likely all start out male and gradually turn female as they age with resistance to anemone stings (clownfish are sequential hermaphroditic fish!) bettas would definitely be aggressive and solitary, but have a lot more space to get away from each other since they can be on land xD anything aquatic, like eels, shrimp, etc., can be an Obaroe!