Saniclean is an acid-based sanitizer that is similar to Starsan but without the foaming action.
Saniclean's contact time is longer than with Starsan (2-3 minutes) and you need to use twice as much (2 oz. per 5 gallons). Use Saniclean for circulation sanitizing with a pump or other applications where foaming is undesirable.
Remember to look at disposal requirements for both of the chemicals when using.