Understocking?

I don't think it is possible to give a fish too much room, I would think its like saying a dog could have too big of a yard. A yorkie may not need a 10 acre yard, but he would sure have alot of fun in it!!! That being said, with that big of a tank, you could happily have lots more fish and still be understocked and keep all the fish very happy

You can be understocked but that is not a problem. Your tank may look empty and you may not have the movement of fish that most people like to see. But it is healthy for your fish and easier to maintain.

I don't think understocking is possible. The reason is that 'understocking' implies it's the opposite of 'overstocking', and somehow a bad thing. There's such a thing as stocking lightly, but there aren't any downsides to that. I guess it depends on what you expect from your tanks--I don't want a incredibly busy tank where a shy fish is ignored because the boisterous fish are always in the spotlight. I like having to look around a bit for my fish.

Of course, I also have a 120 SW setup that currently has 1 7-8 inch burr fish and 1 4-5 inch angler. :huh:

Don't listen to them if they're implying it's a bad thing. As pointed out, you can't really give an animal "too much" room. The more the better. Usually, people just want to put more in a tank because they find it visually uninteresting or there are species that they would like to have.