Star San

if i mix up a batch of this in a 5 gallon bucket - how long can i keep it and have it still work?

If it’s sealed after use, it should last several weeks. I store mixed star San in gallon jugs and test the pH prior to use. If it is anywhere in the 2 to 4 range you should be good. Dispose of it when it gets cloudy.

The ph needs to below 3 for it to be effective.

http://www.basicbrewing.com/index.php?p ... radio-2007

Listen to the podcast from March 29, 2007 for an interview with Charlie Tally, the creator of Star San.

Maybe I need to listen to the podcast again. I know Charlie mentioned cloudiness as a visual sign that it may have lost effectiveness, but I don’t believe that’s the main indicator. I use tap water for mine, because I’m too cheap to spend $4-5 on bottled water for a batch. It’s cloudy from the beginning, because of the ions in the water. But as long as the pH is within range, I keep it. I’ve kept StarSan in a sealed keg or bucket for months with no problems.

I reuse star san for months, too. It’s cloudy from the start, but the pH stays below 3. Every month or so I top off with more water and some fresh star san so that helps keep it viable, too.

Use distilled water and it will last a long time. I mix in a 32 oz spray bottle with distilled water. For brew days or transfers ill mix up a half gallon or full gallon with tap water and dump it when I’m done.

spend the 3 or 4 bucks on distilled water it lasts a long long time. Probably only do a few batches a year and thats because I am running out not because it is bad ph wise

I always fill a mason jar or 2 whenever I have a batch of star san mixed. Dump and refill next time.

If it’s cloudy, try using distilled or RO water next time.

The cloudiness in itself doesn’t hurt anything, as long as the ph is below 3. The cloudiness is a sign that the acidic star san is reacting with the minerals in your water and causing them to come out of solution. Its a sign that you have hard water, but only in extreme cases does it actually mean your star san is no good.

Even if the pH is greater than 3, you can simply add more concentrate until it is below.

Star san made with distilled or RO water will be more stable and last longer, but this isn’t strictly necessary. Even if you have hard water it will work fine provided you add enough concentrate.

This is all paraphrased (from memory) from the pod cast linked above.

I just had RO water used for Star San turn cloudy. Makes me wonder about my RO source.

You can purchase a total dissolved solids meter to monitor your ro system performance. They are fairly inexpensive.