I am getting a 75g aquarium tomorrow off craigslist. I started buying polypterus and can not stop! I now have 2senegals (one is albino), 1delhezi, and 2Endli. All are right at 3 inches and are currently in a 20 long. They all look happy but I know are going to grow up fast. I want to eventually collect a few more polypterus species. Can the 75 hold more when they are all grown? The bichers are the only fish that are going to be in the tank.