depth tank ratio to fish length opinions

[henward]

just wondering, for the MFKs out here, what sort of ratio do you personally abide by when keeping monster fish.
example, say the tank depth front to back is 50 cms, what maximum length fish would you put in a 50 cm tank?
see, i have seen people say, you can put a fish, and the depth should be 10 - 20% more than its length, some say should be more.

 

[badisbadis101]

while i do not personally keep any fish that would ever encounter that problem, in my opinion it depends on the fish. For example, an arowana could probably get away with a less wide tank than an equally sized gar, simply because the arowana has a much more flexible body.

 

[Bderick67]

Ya it does depend on the type fish. Ideally 1.5x the length of the fish would be minimum, but not always practicle.

 

[badisbadis101]

i agree - but again it depends on the fish. I see no problem keeping a 3ft arowana in a tank that is only 3 ft wide, as long as its other needs are met. But a 3 foot gar? probably not. And in the case of say a tiretrack eel that is 4 feet long, it can definitely thrive in a tank that is not four feet wide - 2 feet would probably be more than enough