Serpae Tetras - How Do I Stop The Fin Nipping?

[aaronnorth]

can't really do much with this tank it's too small I really would like to have a lot more fish

it is never ending, when i bought a 180l, i thought this is plenty big enough, easy to maintain, and now i am want a 240l (which in my mind i know it still wont be big enough in the future) but small steps is better sometimes!