Matt are u going to have a species only tank or a community tank; in a species only tank you could put 1 male and 2-5 females depending on whether your putting in Northern Longear (which max out at4-6inches or Central or Louisiana Longear which max out at 5-9 inches long. I also recommend structure (some type of plants, rocks, driftwood) and some dithers.
It depends on what species/subspecies of the longear complex. Northern Longear don't get big, max out at 6" but 3" is the average size for adults. They are less aggressive than Central Longears.
the most beautifull fish in the world IMHO, but they are the most aggressive Longear and can max out at 7-9 inches; I would go with just one male and a couple of females.