在线水质硬度计所测水硬度，又称地下水硬度，指水中Ca2+、Mg2+离子的含量。即水中的碳酸钙含量，烧开可形成水碱。

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　　NEIMESHIYONGYINGSHUIDEWEIHAIYOUNAXIENI?XIAMIANJIURANGWOMENYIQILAILEJIEYIXIABA。

　　1、SHUIDEYINGDUDUISHENGHUOJIGONGYEYONGSHUIYINGXIANGJIDA。GUOYINGDESHUIZHUSHIBUYISHU，XIDISHIFEIZAOQIMOSHAO。

　　2、YINGSHUIYONGYUZHENGQIGUOLU，YISHENGCHENDIANJIECHENGGUOGOU，BUJINLANGFEIRANLIAO，YOUYIYINQIBAOZHA。

　　3、ZHANGQIYINYONGGAOYINGDUDESHUI，HUIYINQIXINXUEGUAN、SHENJING、MINIAOZAOXUEDENGXITONGDEBINGBIAN。

　　4、SHAOKAIDESHUIKOUGANCHA，QIECHANGCHANGZAOCHENGHUDIJIEGOU。YANZHONGYINGXIANGFANCAIDEWEIDAOHEZHILIANG。

　　5、MUYUSHI，TOUFA、PIFUCHANGYOUGANSE、FAJINDEGANJUE，SHANGHAIPIFUJIASUSHUAILAO。

　　6、XIDIYIWUSHI，LANGFEIXIDIJI，QIEYIWUBUYIXIJING，XIHOUDEYIWUFACUIFAYING，BINGCANCUNYOUXIDIJIDEWEIDAO。

　　7、CANJU、JIEJUSHANGCHANGCHANGHUICHUXIANSHUIZI、BANDIAN，XUYAOJINGCHANGQINGXI，SHUICHISHENZHIQIANGBISHANGCHUXIANSHUIGOUDENG。

　　8、RESHUIQISUIZHESHIYONGSHIJIANDEZENGJIAERREXIAOLVJIANGDI，ZHEIYESHIYINWEIJICUNDESHUIGOUZENGJIALE，BUJINLANGFEINENGYUANHAIXINGCHENGLEBUANQUANYINHUAN。