Running this by the tang police

Also, when I had my 3" Kole Tang in my RSM (36" across), he could swim across the tank in about half a second with no effort, and did so nearly constantly.

 

Ohhhhh I didn't see the dimmentions of the tank..
And for some reason I thought this was a 55.. Lol I guess I was reading to fast.

Then nvm of what I said.. Well no.. Actually what I said was correct but it applies to 4footed tanks. oops.

So then Instead I would look into wrasses and angelfish like someone mentioned.

 

I wouldn't put a tang in a tank that size.

 

Well thank you guys. I was leaning towards no, I just was thinking with the eminent upgrade maybe. Well I guess the little african flameback will be the "trophy" fish

 

Same with my 48"
It isnt nesesarilly the gallon(age) of the tank, its the length and width. If a biocube were 4ft long and a foot wide then you could put a smaller tang in there.

 

I had my kole in my 90g. 48x 18 and 24 tall. It never was obviously bored in the 90g. if any fish swims in really noticeable patterns, and acts like it wants more space, then it does need more space. Typically that is. Sometimes you can get a neurotic fish that won't take to captivity that well and exhibits those weird behavior even in tanks that are a couple hundred gallons.