Hey
@Slocke my baby monster has went from 9" to about 20" in 9 months. They will grow fast the first year to 2 years. Nothing in a 55g will live, mine is in a 210g, the same footprint as 180g. Mine happens to be on the shy side, I;ve seen them much more aggressive, but he is still a baby. I keep tinkering with the idea of a few triggers to bring him out of his shell, but the initial plan was as a solitary fish. Only large aggressive fish will have a chance with this eel. A small juvi is not the same as a mature eel.
I would re-measure as I have never seen a tessa that small, at 9" everyone said they had never seen one that small, I never have.