My females will flare for a day or so when I add a new one. Then they stop. Give them some time but keep an eye out for violence.
Your tank might be a bit over stocked especially as the fish start to grow bigger. Test it weekly and do more than one water change a week if it gets unstable.
PS tetras are schooling fish, one tetra might not be happy on his own.
Last edited by registereduser; 02-16-2013 at 10:16 PM.