Yellow/Purple Tang Tank Size

I am looking into possibly getting a Yellow or Purple Tang in 3-5 months for my tank, my question is: is this even a remotely good/doable idea? I have a 40g breeder (36"x18"x18") and plan to stock sparingly for room for the tang (<6 small fish, including the tang, an ORA Dragonet, Yellow Watchmen Goby, maybe a small Fuzzy Dwarf Lion but will need to look into that more, and a few small fish for color) I have also left open swimming room and good sized hiding areas for it. I have lots of the algae they love too. I have spent about 2 weeks researching Yellow, Purple, and Kole Tangs and the only info I have trouble on is tank size, apparently min. tank sizes range from 30G to 125G so I figured I'd ask people with more 'one on one' experience. Any way I can make this work? As a side note: I plan to upgrade to a 200+ gallon in 2-4 years. Thanks everyone for the help.

 

A 40g tank is too small for any Tang.

 

Alright, thanks.

 

Dwarf lion might snack on smaller fish.

 

This size of tank would not work for any tang
However, a 200+ gallon tank would be great for most tangs

 

Ya, I will be trying to find the best one I can for eating frozen foods and good with tank mates, luckily my LFS lets me set some fish on reserve so I can check behavior.

Hopefully I can snatch a 280G on CL for 400$ if the guy responds.

 

That would be great
A 280 gallon tank would prove to be expensive, but it would allow you to have an extremely wide variety of fish.