Me calling out this post is not ok to put down like this is you calling my post hateful. Wow.
If you don't mean it, then don't use the word hate. It's a rather strong and offensive word.
And yes, as you noticed, I did take offence.
I think you should look at the behavior of a fish to see if it's happy or not. Not all tanks that are the same size have the same scape and with fishes also they are different.
Yes, a 15cm fish that is used to swim a lot, even though it may not swim very fast needs its space.
This is a tiny tank with a big (large growing) fish and a lot of scape.
Besides who do you think is able to tell that a certain fish should be placed in 20 or 40 gallon?
We as a community do. If you can put forward valid arguments why 60 by 45cm is plenty of space to properly house a butterfly fish long term, then give them and we can discuss. Don't start putting away opinions as "hating".
If I follow you reasoning you are never going to a zoo in the Netherlands because of all the animals and reef tanks are way to small to house them. For example the sharks in the zoo's the tanks are no match to the miles these animals travel in the wild.
Views of what is acceptable change. A few decades ago it was perfectly normal to flick a whip at a lion in front of an audience and make it jump trough a hoop...
Oke, lets do the math. A 3 meter shark in a 1 million liter tank has way more room to do its thing than an butterfly fish in a 0,000125 million liter tank. 3333 liter per cm of shark versus 8,3 L/cm of fish to be precise. So that's about 400 times as much. Even if the shark was housed in a "tiny" 100.000 L tank, it would still have 40 times as much space.
This copperband's home is like housing a 3 meter shark in a tank of about 3 by 1 by 0,8 meter (2400 liters).
So, your reasoning conflicts itself. Also, it is based on a fallacy. Namely, all or nothing reasoning. If you cannot meet all the needs of an animal, then its not necessary to meet any.
Lastly, if the topic starter finds my reactions offensive or inappropriate he/she may say so.
I will reply cordially.