nice longnose, i highly suggest against that mix thou, longnose gars are known to break their backs far more often and be more skittish than other gars. the tankmates you currently own are also notorious for being boisterous & aggressive
Not only that. Longnose gars have a hard time swallowing it's food than other gar species. I hand feed mind I just to insure it gets all the food that it need. I also watch it carefully as other fish will just snatch the food out of it's mouth. Used to have two longnose and one died of of infection when my oscar stole the food that is hanging out of it's mouth and broke the lower jaw.