I wouldn't, because the oscars will EASLY outgrow the EBJDs in about a month or two. EBJDs are the "runts" of the JD breeding batch typically, so because of that they grow much slower and are much more sensitive and prone to stress and disease. Oscars on the other hand can grow at a rate of 1.5" per month and are very aggressive eaters (mine was). I just think it's a bad combo personally, and yes tank size does matter