Why do hobbyist have frag tank?

[BigEZ77]

Fixed it for you lol!

Ain't that the truth!

 

[thomas.torode]

Why do marine hobbiests have fish tanks just for coral?
Dude I honestly have no clue.

On a serious note, I do know it helps grow coral fast without effecting other inhabitants of a fish tank. And it can be profitable $u$

 

[TangingOut]

I have a frag tank completely separate from the my DT reason is AEFW, red bugs, and the other unwanted hitchhikers. Plus it allows me to let the coral grow with near perfect conditions. I get 10x the growth in my frag tank than I do my display and they run at the same parameters.

What variables do you believe contribute to the extra growth?