Man he's small, gotta be like 4"? I wish I coulda got mine at that size, would've saved a lot of lives lol, got mine at 8" and he grew quick and ate a lot of tankmates. Glad to hear the Oscar is doing better in the bigger tank. I advise putting the curu in a little smaller than the other wolves so they can hopefully establish a pecking order in their favor, as you may have read, curus seem to be the most problematic with same species and other wolves. But I wish the best of luck to you, I think it's doable. I had mine with a mala for awhile till the mala broke his jaw on decor I believe, and then jumped from the hospital tank while I was at school and perished after two days being back in the hospital tank. Your tank is slightly larger by 2 ft which may also help and you have more fish to disperse aggression. It was pretty much only him the curu and odoe, and three bichirs (7-9") which were completely ignored by everyone. I look forward to updates on everything. Good work with the Aquascape as usual, maybe I'll be that good one day if I venture into plants lol.