I won't lie, I've tried it once after 1.5 weeks and it still tasted good. It was slightly flat, so I set it to 10 psi on my regulator connected to my paintball tank, and the next day it tasted even better. Kind of a hybrid carbing between sugar and force carbing.
There are a couple of ways you can hook it up to a CO2 tank. I've never used a tank your size, but I'm sure you could make it work.
Here is one way, which I have not tried:
https://www.homebrewtalk.com/f51/home-draft-mini-kegerator-231800/
Another way is to directly connect it to a paintball tank via a regulator, which is what I did. I spent about $65 with this setup (regulator, TAD adapter, and paintball adapter), but it works well for me. You can either purchase a paintball tank adapter and connect it to the regulator:
http://www.rebelbrewer.com/shoppingcart/search.php?search_query=paintball&x=0&y=0 However, since you fill paintball tanks, you probably already have a paintball CO2 adapter and you can use that to connect to a regulator similar to this setup:
http://brewing.lustreking.com/gear/paintballco2.html. I also had to purchase a TAD adapter from ebay,
http://www.ebay.com/itm/16-gram-CO2...885?pt=LH_DefaultDomain_0&hash=item231264f255
It's just like this guy's setup:
http://www.youtube.com/watch?v=RPw0H0jT14k
I needed a regulator anyway, so it didn't bother me to spend the money.
FYI, I was able to purchase a Coors Light Draft system, which is similar to the TAD. You get a 1.5 gallon bottle with a tap for $15 to $17, which isn't a bad deal, considering it's also filled with beer. Then you will have an extra tap.
I hope this helps and I was somewhat clear.