How long can StarSan stay (stored) inside a keg?

[Panderson1]

If i fill a keg w StarSan and seal it off and let it sit a month, would that be OK? If seen it do some weird stuff to other random objects and hose lines. But stainless steel? no rust or anything? just wondering...

 

[daveMN]

I keep a dedicated keg of starsan in my brewery and it's really handy. It sits in there for months. I'll replace it periodically, but well over a month, to your concern.

 

[NeoBrew]

I've been told that making it with PR or distilled water will make it last longer. It apparently starts to look milky when it is past it's useful life. If you are the sciency type you can also test the PH of it. I don't remember what value it is supposed to be under, but I'm sure you could Google it.