Star San contamination

[Minbari]

I thought SS is just dilute hydrogen peroxide? Maybe some phophoric acid as well both are harmless in dilute quantities and frequently used in FnB industries. It might have terminated the yeast.

IIRC star san doesnt last long when you have mixed it up - a few hours maybe then its inert (like peroxide)

There is no peroxide in it.

From Thier website:

Phosphoric acid: 50% of the ingredients in Star San
Dodecylbenzenesulfonic acid: 15% of the ingredients in Star San

It will last a long time. As long as the ph remains below 2.5 or so. It is still good. i keep mine in a bucket for 6 months +

 

[Donoroto]

I put in only enough starsan to just cover the end of the blowoff tube. If it sucks back, the liquid level drops and lets air into the tube instead of liquid.

2 cups in 3 gallons? Probably fine.