Change the rules..

its like what steve said, If an experienced tank person overstocks a system then he will know what to look for and take care of the problems that will arise, but the problem there is a person with little experience sees an overstocked tank and then overstocks there tank and everything dies because they didn't understand how to care for a overstock tank (its allot of work) then they quit the hobby because of frustration.

as far as the no room to swim you will only get theroy's on this because really unless you can ask the fish there's no way to determine the psychological affects on a fish. But I think it falls down to common sense also. Like I wouldn't put a tang in a 20 gallon.
well that's just my opinion, hope it made sense.

 

some great opinions here, Im enjoying this.. I feel as though I could have 5 b/g chromis and my royal gramma all living in harmony in my system as long as I keep a somewhat wet skim.. JMO

 

yea +1 on the tang not going into a 20 gallon lol

 

Your the man!!!lol I guess thats the truth

 

I follow this logic as well.

A fish that likes a lot of room to swim in, will need a bigger tank. I also think the incehs of fish per gallon "rule" is not realistic, since as you stated, a 5" tang eats and excretes far more than 5 neon gobies.