I have been keeping two Black Velvet Oscars for the last six weeks. When I purchased the pair they were roughly the same size and difficult to tell apart. They acclimated to their new environment -- 29
Gal Tall -- very well. They were eating and staking out territory within a day.
As is almost always the case, they were aggressive feeders and the seven Diamond Tetras that share the tank definitely clear out when feeding time started. One of the Oscars (Leo) immediately began showing dominance in feeding and began becoming very territorial (even by Cichlid standards) to the point that he(?) would chase off the other Oscar (Daphne) during feeding. Not surprisingly Leo began growing significantly over this span and is now 3x the size of Daphne in a little over a month. (See pics)
I am familiar with one fish asserting dominance in this species -- but my question and concern is whether the smaller Oscar is suffering. Daphne hides behind a large rock for most of the day. When s/he comes out Leo is all over her. I do not know the genders - just guessing. Anyway, this situation is not getting better and Leo is more aggressive each day. Daphne seems listless and stressed, but she does feed when she can. Is it time to put Daphne in her own tank permanently?
Appreciate any thoughts.