If you mix with distilled water, it will last for a long time. I usually keep a revolving batch that I add to whenever the level gets too low, 1-2 gallons at a time. If the pH goes above 3.5, you can add a couple of drops of undiluted StarSan to bring it back down. And when it gets too much debris at the bottom of the bucket, you can rack it off into a new bucket.
Only once or twice a year do I actually dump it out and make a fresh solution. I have also never experienced the cloudy StarSan that I hear people talk about, so I guess distilled water is working.
Read my brewing blog here! Last of the Zyme Lords
BOUSIRIS BOUERY - Home of the Zyme Lord
"His is the House that Malt Made."
- James Joyce
Old Took's Rethe IPA
Weiss Blau Weiss Bavarian Hefeweizen
- empty tap -
Le Petit Plésiosaure Summit Saison
Anna Livia Dry Stout
Kessler's Rampage London Bitter
unnamed ginger metheglin