star san

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Well-Known Member
Mar 14, 2007
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Star san is good until your ph reaches above 3 right?

I never checked it before and mixed some up today and tested it with a ph strip and it was way above 3 with my tap water, so it has never been effective this whole time I have been using it?
i think it will be effective when mixed but will not store well above 3.
i mix mine with distilled water to avoid the problem
To be effective (i.e. lethal with 30 - 60 seconds of contact time), the solution must be at a pH of less than 3.5. If you have very hard/alkaline tap water, the recommended mixing ratio (1 oz/ 5 gal) should still get you below a pH of 3.5. However, as was mentioned, it won't store very well (you will notice that it turns cloudy in a while).
I had to mix almost double the amount to get a gallon of water down to below 3
Wow. That doesn't sound right. Email Five Star Chemicals and get their advice. They are great with customer service.
I have to think one of two things:

1.) You got a bad batch of Star-San
2.) Your water is really f-ed up.

Seriously, if the 1oz5gal ratio is STILL yielding >3 pH solution I would NOT brew another batch of beer with your water.

I'd blame the star san first though, since water that bad could probably chip teeth. :)
i dont brew with my water but i use it for the starsan mixture. I remembered the first reading I took was tyring to mix just a gallon of it so I could have been slightly off on the amount. But on other forum I have brought this to, some people with high ph just have to add more starsan to drop it down. I had to add more starsan and my reading went down also