I'm relatively new to goldfish, so don't consider me an expert by any means, but I think instead of just listing thisbreed=thismanygallons, you should list them to house a small group (since goldfish are social and shouldn't be left alone, IMO) and a larger one. mmmmm.....that doesn't sound right. I guess what I'm trying to say is that if they want to keep 2-3 of a variety, they need a minimum of this size tank....versus someone who wants to keep 5-10 or an even bigger group, develop a rule of thumb. Often times, people mix orandas, and ryukins, and moors, and whatevers together when they have a large tank. For instance, one I found used commonly is 20 gallons for the first fancy and 10 for each after with a 30/20 ratio for the long-bodied varieties. Obviously, this is more of a minimum approach, but that should be the kind of info you're providing, I think. Ultimately it's up to the aquarist whether they want to provide more. And article shouldn't be opinions on what you feel is appropriate housing, but just enough for them to live healthily and happily (not just survive). I feel like I didn't word this well, but I hope you understand what I mean.