I wouldn't want to get into an argument with someone, but my opinion is that 6 x 2 x 2 tank is only big enough for two adults Oscars. That is the exact dimensions of my tank. I can't possibly see how you can keep eight adults Oscars without having water quality problems, even with really good filtration. However, if they think they can manage it, then who am I to argue, I just wouldn't attempt it myself, and I certainly wouldn't recommend keeping any more than two Oscars in a tank of this size. You really should be looking at something that is over 400 gallons