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pH meters can range from $30 to $500+. The problem with many of the cheaper pH meters is that their reliability and longevity are often questionable <ref name="ajdelange">[http://www.homebrewtalk.com/showthread.php?t=302256 AJ Delange. Homebrewtalk Thread. Posted 02/08/2012. Retrieved 04/18/2015.] </ref>. Commonly, two pH meters are recommended by by trustworthy sources (AJ Delange and Kai Troester).