Stocking Aquariums

[elc02]

I'm new to the aquarium hobby and I'm so confused on how people calculate how much space they need for different species for different needs. Every time I read about I just get more confused. Say you have a yellow tang, powder blue tang, blue tang, clown tang, naso tang, convict tang and a purple tang. How would you work out how much space you need?

 

[Stealthreefer]

You want 6 feet plus for them to swim freely.
Its really not about gallons, it's about them being able to zoomie in an enclosure big enough that they aren't bouncing off the sides.
We used to say an inch per gallon in the olden days. That was about our filters sucking, not actual science.
With modern filtration you can keep a huge fish alive in a tiny tank now, but what kind of life is that for a fish?
If you have ever seen Oscars that get huge in a tiny tank.

Marine fish need room to go crazy and room to hide.