Change for the worse in Star San longevity? At least in my new bottle...

General Homebrew Discussion
21

This is my H2o profile in Idaho Falls. In the early days when i didnt pay attention to my H20 brews were just off. My starsan immediately clouded when poured into my tap water. Hell $2 for RO water has made a huge difference. It last 3 to 4 months for me and i brew often.
Calcium 66
Sulfate S04-s 12
Magnesium 20
Sodium 27
Chloride 18
Hardness 262
Alkalinity 224
Idaho Falls PH 8.1

22

I’ve never heard of an acid that looses it’s acidity during storage.

23

I know this is an old thread, but I have noticed the same thing.  My Star San solution with carbon filtered tap water  in forest, Virginia used to stay clear for months.  Starting in early 2013 I noticed it would be cloudy within days.  I measure the pH and I continued using the Star San solution as long as the pH did not go above pH 2.7.  I did shorten the time that I keep the solution, but I do not know if it was necessary.  I never had any problems with contamination.

My conclusion is something did change with so many from different areas reporting the same thing.

24

FWIW, mixed with distilled water, I haven’t seen this.

25

With tap water my Star San will cloud up pretty much instantly… Within an hour for sure.  I use RO water (assuming I wasn’t too lazy and have some made up…) It lasts for months with RO water.

I ran an experiment a while back with 2 mason jars of star san (made with RO water).  One covered and one uncovered. The pH of both remained about the same for quite awhile. Though as the uncovered one started to have water evaporate the pH dropped.  They both started at a pH of 2.14 and 5 months later the volume of the open jar reduced by about 7/8ths and had a pH of 1.87 and the sealed one had a pH of 2.24.

I have noticed on large batches I make the pH does rise and I believe this is due to the fact that you’re sticking stuff in there all the time which is neutralizing some of the acid.

26

I use RO and keep it until the level drops below a usable amount or it gets dirty.

27

Softened water (ion exchange as noted by Martin) with Star San stays good for me quite a while, but I have gone to changing it out after a week or two, just to be safe.  I don’t have any problem with that.  I occasionally go with distilled, and keep it around longer in smaller quantities like a gallon.