Star-San works great for almost all sani applications aside from CIP. If you'd like to use it as a tank sanitizer I'd go with the Sani-Clean product. As it was explained to me, it is the same product w/ an anti-foaming agent added.
I like the *-San products because they are acid based. After any alkaline soak, we quick rinse and dunk into star-san before air drying. I've found that it's tough to get all the cleaning product off of small parts without intensive rinsing.
I'm not trying to sanitize every part I put away, but instead looking to have fully removed any extremely high pH substance away from the stainless.
Another wonderful thing about acid based sanitizers is that they kill at known pH levels. Star-San, and Sani-Clean for instance, will kill bugs @ 3.5 pH or below. The dosage rate for these products are based upon an average water profile. Your water maybe nice enough to only use .5 oz/5 gals, or you may need more. Spend the time to titrate a solution to your water and use that amount. Saved a lot of chemical at our shop.
That being said, it's always a good idea to switch up your sanitizers on a fairly regular bases. We use clor-dioxide for CIP type sanitizing for most part, and will change to sani-clean from time to time to keep the bugs guessing.
Swing Tree Brewing Company
300 E. Hersey St. #7
Ashland OR, 97520
boverstreet at swingtreebrewing.com