These Red Rainbowfish are the juvenile size but will grow to be the largest of the group, so you will want to make sure that you have a large fish tank. To be at its best, it needs to be in school of at least 6. This species is extremely social and can be put into a tank with other non-aggressive species. They do enjoy swimming however, so it’s best to have them in an open tank. It will be quite the site to see.