Tangs are swimmers and it is the length that is important not the volume and for that reason I would not recommend keeping two or three of them in a 3 foot tank.
Some fish like angels, kind of 'hang around' and for them volume is important not the length.

There is lots of people on here that have two in 72s and 90s
My tang has more room to swim around in my 3 x 3 cube than most 6 foot long tanks as there is not rocks piled all against the back wall.
Anyway I just asked the question and like I said decided against it.
Mods please close this thread.

I know someone who has a baby Tiger shark in a 90G...I think I may get one too :wink:

I thought you were joking :p

FWIW go with a tang of a different species... For fear of the tang police (and I'm one of them at times LOL) I have a Purple, Regal and Powder brown in my 90.

Albeit my PT is an adult and the PB and Regal are both babies.. I know I will need to either upgrade or rehome down the road.

But it's okay for you to have three tangs in your tank with two over 6" because you have a 6 foot long tank.:lol:

I have two purple tangs in a 120, and have no problems.
I would say they get along better with each other than they do with the regal or wrasses

How do you figure you have more room than a 6' tank? By my calculations the square footage of a standard 125g (72"x18"x20"ish) is 1296 square inches and your tank at 36"x36" is the same amount of square inches, correct me if im wrong. As stated it is recomended at least 6' of length for most tangs some require more. When i put my PBT in my 120g my purple almost killed him.

Closed at posters request