ive had a couple gallons made for months . I put what fits in a spray bottle and use it that way most of the time. It is a contact sanitizer so as long as the surface gets completely wet ,doesnt need to be submerged ,it's treated.
It's a phosphoric acid solution, there is little reason why the pH would change, unless alkaline cleaners, wort, or dirty items were dumped in it. I'd be more worried about the other additives, especially the surfactant, that may have bound and precipitated.
I know it doesn't matter, it just seems like something's wrong.
Depends on your water source, cleanliness of utensils you are putting in the starsan, and I would imagine temperature plays a certain role. I've had some batches last 3 months, some more than 6 months. I always pour some sanitizer in a 2-4 quart stainless steel bowl during wort boils then discard that at the end of boils. I noticed over the years that leaving any kind of plastic ( airlock/hoses) in the sanitizer bucket for any length of time other than sanitizing will degrade the solution and turn it cloudy. A good rule of thumb is as long as your solution is Crystal clear, it's good. If it's cloudy, dump it. You can get cheap pH test strips on Amazon or eBay or even a low cost decent chemical pH test kit which to me is more accurate. Most folks use the Clear or Cloudy rule and do well with it. Cheers [emoji481][emoji481]
Should not be cloudy. Are you using tap water? RO? The best and recommended is Distilled. I know also temperature plays a role. It should be room temperature, not too cold or hot. I've noticed my solution gets cloudy if the room ambient temperature is too cold. Try using distilled water room temperature 68-72° and store it at room temp.
